Anglo-American system of measurement

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The Anglo-American measurement systems have their origins in medieval England and were spread in the area of ​​influence of the former British Empire . The Anglo-American system of measurement exists in several variants and is not a self-contained system of measurement. In addition to the largely lacking reference to the decimal system  , this is the main difference to the metric system of measurement .

Todays situation

Connection to the metric system

The Anglo-American system of measurement - as it is today - is not an independent system of measurement. The Mendenhall Order issued in the United States of America in 1893 abandoned the reference to its own measuring standards and determined the corresponding metric measuring standards as the standard for the basic units of yards and pounds . With the introduction of the unified “International Yard” on July 1, 1959, all countries with the exception of Great Britain made a final changeover to metric measuring standards. Great Britain also took this step with the Weights and Measures Act 1963 .

Use in English speaking countries

In the 19th and 20th centuries, the Anglo-American systems of measurement were officially used in the United Kingdom and its colonies, as well as in the United States . In 1973, Great Britain undertook to abandon the traditional system of measurement in favor of a Europe-wide uniform system, the metric system. In order to make the changeover easier, both measurement systems were to be used in parallel in Great Britain until 2010; this exception was converted into an unlimited one in 2007. The conversion to the metric system met with various opposition in Great Britain (see the citizens' initiative Metric Martyrs ), and the units of measurement of the imperial units are still widespread, especially in everyday dealings among citizens. The situation is similar in Ireland , Canada , India , Malaysia , Australia and New Zealand . In the USA, the Anglo-American measurement system in the variant of customary units (which is based on a historical form of the British measurement system) is still in full use as the main measurement system.

International use

Some Anglo-American dimensions are also used internationally, but often not as an actually measured size, but as a nominal designation. For example, oil is traded on the exchange in the volume unit barrel , but is weighed in tons, and flight altitudes are given in feet, but are actually air pressures standardized to the same reference value. The nautical mile (nautical mile) is not specifically English unit, but a minute of arc of the rounded in the relevant measuring system earth's circumference. Even the customs (inch) is indeed in many countries for certain size constraints in the technology used, but these are almost never real measurements, but as with the 3.5-inch floppy disk , the diagonal of just 90 mm and not 88.9 mm measures, just conventional (trade) names.

Common units

Examples of important and frequently used units of Anglo-American systems of measurement are: Step (yard) mile (mile), oz (ounce), pound (pound), Stone (stone) fluid ounce (fluid ounce), pint (e) (pint) , Quart (quart), gallon (gallon) , acre . The units have been defined differently throughout history. Particularly in the area of ​​the dimensions of the unit, differences between English and US-American variants of the units have developed from this to this day.

Even in English-language science and technology, some non-metric units are still in use today. For Newtonian mechanics, electrical engineering, etc., new units had to be formed or existing ones had to be more precisely differentiated. In part, this was done on the basis of the Anglo-American units in various so-called FPS systems (foot, pound, second), which v. a. distinguish between whether the classic weight units are used for mass (pound-mass) or force (pound-force) . In the English-speaking world there are also some units that can be assigned to the metric system (e.g. nit ) or names (mho) that have not been able to establish themselves on an international level. These belong at best to the periphery and not to the core of the Anglo-American systems of measurement.


For the metric system, there are international standards (e.g. ISO / IEC 80000 ) that describe rigid symbols (without abbreviation points) for the metric units, and these may also be applied to English units in the technical field, e.g. B. "lb F / in 2 " instead of "PSI". Overall, however, numerous different abbreviations (often with a full stop or in capital letters) are or were in use for Anglo-American quantities, which in some cases collide with the SI (e.g. 'nm' for nautical mile or nanometer). Exponentiations are usually expressed by prefixes ('sq.' And 'cu.' For square (d) and cube (d) ), while the resolution of linguistic ambiguities (e.g. 'avdp.', 'Tr.' And ' ap. 'to pound and ounce) are more likely to appear as suffixes. A plural 's' is often added to the abbreviation, while the unit symbols of SI units always remain unchanged. Few units can be denoted by non-letter symbols, v. a. the pound with # and units such as feet (′) and inches (″), which are often used with and next to each other, as well as the archaic apothecary's measurements ( scruple ℈, dram ʒ, ounce ℥, pound ℔). Since many names are monosyllabic, they are often simply spelled out in size specifications.

Units of length

Ratios of the Anglo-American units of length to one another

Formula symbol of length : l or s


Since July 1, 1959, standardized definitions apply to the Anglo-American units of length (and also units of weight). Previously, the stipulations in the states of the British Commonwealth and the USA differed extremely slightly from one another. The standardized system of measurements was given the additional designation "International", which is rarely given.

Length measurements
unit German Abbr. size metric size
inch inch in. 2.54 cm
foot foot ft. 12 inch 30.48 cm
yard step yd. 3 feet 0.9144 m
mile mile mi., m. 1760 yards 1,609.344 0m

US land survey

The units of measurement chain and link are named because land was actually measured with such chains up to a hundred links.

In order not to have to convert the length and area data to the new international dimension due to the standardization of land and property dimensions in 1959, the old dimensions in the USA retained their validity exclusively for this purpose and are used as "survey measurement" or " surveyor's measurement ". The basic unit is the US survey foot , which is defined as 1200/3937 m ; thus the international foot is 2  ppm , about 0.6 micrometers, shorter than the US survey foot . According to the National Institute of Standards and Technology , the US survey foot is declared obsolete with effect from January 1, 2023 and should no longer be used after this date.

As an alternative system for floor measurement, " Gunter 's measurement" with the units of length link and chain was created in England in the early 17th century . Since the floor area calculated from this in square chains has a decimal relationship to the target unit acre , the area calculation with the means at that time is less cumbersome than with the conventional non-decimal units. In North America in particular, the 100-link, 66 feet (approx. 20 m) long Gunter's chain was widely used for land surveying. In addition, there was another less common classification for land surveying chains according to Jesse Ramsden , called “engineer's measurement” , in which one link in the chain corresponds to exactly one foot .

"US survey" measures of length
unit German Abbr. size Metric size
link Chain link left 0.66 feet 0.000,2011684 m
foot foot ft. 0.000.3048006 m
rod / pole / perch rod approx. 16.5 feet 25 left 0.005.029210  0m
chain 1 Chain ch. 66 , 0feet 04 rods 0.020.11684  00m
furlong Furrow length 2 For. 660 , 0feet 10 chains .0201.1684  000m
(statute) mile mile mi., m. 5280 , 0feet 08 furlongs ≈ 1,609.347 0000m
1Since a rectangle with the size 1 chain × 1 furlong has exactly 1 acre area, the term acre breadth ("morning width") is also used for the chain .
2Another German name for furlong is eighth mile .

Units such as link, chain or furlong are rarely used.

Since some units have been redefined over the course of time, when converting historical measurements, it is important to note which definition was used at the time and how precise both are.


The international nautical mile ( international nautical / sea mile ) since 1929 (USA until 1954) to km 1.852 set. The cable length ( cable length ), consisting of 100  Fathom ( yarn ) corresponds with one-tenth of 185.2 m nautical mile. It is used, among other things, for depth measurements. There are other definitions for the cable length , such as the almost equally long 100  fathoms (182.88 m), or 120  fathoms (219.456 m) for the US Navy . Fathoms (abbreviation f, fath, fm, fth, fthm) are only (still occasionally) used to measure the water depth or as an auxiliary unit in nautical charts (10-threadline, 20-threadline etc.) without being explicitly named; shackle or naval shot practically no longer at all, although the British measure was not increased from 12½ to 15 fathom until 1949 for the purpose of approximation  .

Before the introduction of the international nautical mile in 1929, the British sea mile (also Admiralty mile ) of 1,853.184 m was in use. This sea ​​mile is exactly 800  feet longer than the land mile .¹)

¹) In contrast, mil in nautical science means the angle measure “ line ”).

Nautical dimensions
unit German Abbr. size Metric size
fathom Thread (for plumbing ) or  fathom fm., fth. 0006 feet 0.001.8288 m
shackle (UK), shot (US) 0090 feet = 15 fathom 0.027,432 0m
cable (length) Cable (length) cbl. 0600 feet = 100 fathom 0.182.88 00m
110 sea ​​mile 0.185.2 000m
nautical mile (admiralty)
sea ​​mile (admiralty)
until 1929/1954
Nautical mile (Admiralty) nm. (adm), sm. 6080 feet 1,853.184 0m
nautical mile
sea ​​mile
from 1929/1954
nautical mile NM 1,852 , 0000m
nautical / sea league nl. 3 sea mile 5,559,552 0m

Other length dimensions

Other rare, old and special sizes
unit German Abbr. size meter domain
Gauge 1100,000 inch 0.254  µm 00 000.000000254 m Film thicknesses
twip twp. 11 440 inch = 120 point 17.6  µm 00 000.00001763 8 m Typography, DTP
mil (US), thou (UK) 11000 inch 25.4 µm 00 000.0000254 m technology
mickey 1200 inch 127 µm 00 000.000127 m Computer technology
point Point pt. 172 inch = 112 pica 353 µm 00 000.0003527 7 m typography
(shoe) ounce 164 inch 397 µm 00 000.000396875 m (fine) leather
(shoe) iron 148 inch 529 µm 00 000.0005291 6 m (thick) leather
line line ln. 112 inch 2.12 mm 00 000.00211 6 m Typography, craft
pica Pica pc. 16 inch 4.23 mm 00 000.00423 3 m typography
barleycorn Stye   13  inch 8.47 mm 00 000.0084 6 m old
digit, nail foot finger 34  inch 1.91 cm 00 000.01905 m old
finger (breadth) finger 78  inch 2.22 cm 00 000.022225 m old
stick 2 inch 5.08 cm 00 000.0508 m
nail yard nail 2 14  inch = 3 digit 5.72 cm 00 000.05715 m
palm Hand (palm)   3 inch = 4 digit 7.62 cm 00 000.0762 m old
hand, (palm width) A hand's breadth   4 inch 10.2 cm 00 000.1016 m old, water level, horse size
shaftment (small) range   6 inch 15.2 cm 00 000.1524 m old, textile
span (large) span   9 inch = 3 palm 22.6 cm 00 000.2262 m old, textile
quarter Quarter yard   9 inch = 14  yard 22.6 cm 00 000.2262 m
cubit     18 inch = 12  yard 45.7 cm 00 000.4572 m old, textile
pace (US), step (UK) step 30 inches = 2 12  feet 76.2 cm 00 000.762 m military
ell Cubit 45 inch 1.14 m 00 001.143 m Textile
grade, geometric pace (Double) step   60 inch = 5 foot = 2 pace 1.52 m 00 001.524 m military
rope rope 240 inches = 20 feet 6.10 m 00 006.096 m Nautical
skein 4320 inches = 360 feet = 120 yards 110 m 00109.728 m Textile
league League hour lea., l. 190080 inch = 5280 yard = 3 miles 4.8 km  4828.032 m Nautical
spindle (Spindle) 518400 inch = 14400 yard = 120 skein 13.2 km 13,167.36 m Textile

Sketch of the measures of length going back to the human body

Coded length dimension designations

For the thickness of sheet metal , the diameter of wood screws , drills and electrical wires as well as the length of nails , the dimensioning of the diameter, length or thickness is not always given in units of length, but with a designation derived from a formula or a Table the actual dimensions can be determined.

  • American Wire Gauge (AWG) : Wire diameter for electrical cables
  • Imperial Standard Wire Gauge (SWG) : Comparable to AWG - outdated
  • Drill Wire Gauge : drill diameter
  • Standard Sheet Metal Gauge : sheet thickness
  • Penny Size (d) : nail length
  • Wood Screw Size : diameter of wood screws
  • Diameter and thread pitch for screws according to the Unified Thread Standard (UNC / UNF screws)

Units of area

Formula symbols for the area : F , A


The length units standardized in 1959 result in the corresponding general area units.

General area dimensions
unit German Abbr. size Metric size
square inch Square inches in² 00 000 00 0.00064516 m²
square foot Square feet sq.ft. ft² 144 in² 0.09290304 m²
square yard Square yards sq.yd. yd² 9 ft² = 1,296 in² 0.83612736 m²
square mile Square mile sq.mi. mi² 3,097,600 yd² 2,589,988.110336 00 m²

Units of land area

In practice, only the units acre or square foot are used for land areas . The unit square mile is used more in geographical contexts. All other units of land area such as square rod are no longer used and are actually only of historical importance.

The land area units in the USA are based on the US survey foot , otherwise on the international foot . Thus there are two different systems of measurement for land areas. However, the size differences are extremely small. The square mile (≈ 2.6 km²) based on the US survey foot is around 10.36 m² larger than the international foot .

Area measurements for land or property sizes
The basis is the US survey foot or the international foot
unit German Abbr. size Metric size (US survey foot) Metric size (international foot)
square foot Square feet sq.ft. ft² ≈  0.000.09 m² ≈ 0.09290341 m² see general area dimensions
square rod
square perch
Square rod sq.rd. rd² 272 ¼ sq.ft. ≈  0.025.3 0 only of historical importance
square chain 16 sq.rd. 4,356 sq.ft. ≈  0.404.7 0 only of historical importance
rood Quarter morning ro. ¼ ac. 10,890 sq.ft. ≈ 1,012 , 00 English plot size - historical
acre tomorrow ac./a. 160 sq.rd. 43,560 sq.ft. ≈ 4,047 , 00 ≈ 4,046.872609874 m² 4,046.8564224 m 2
square mile Square mile sq.mi. mi² 640 ac. ≈ 2.6 km² ≈ 2,589,998,470 319 5 m² see general area dimensions

North American land division into sections

In the greater part of the USA and western Canada, during the European settlement phase, the land areas were divided into square areas using orthogonal surveying networks aligned with the cardinal points . Due to the curvature of the earth, there are inevitably deviations from the desired values.

The section covers a nominal area of ​​one square mile or 640 acres (≈ 260 ha). The nominal value of the edge length is one mile (≈ 1.6 km). A section can be subdivided into further partial areas, which in turn are usually square. In the USA the section also includes the areas for the public road network, in Canada these areas are measured separately.
Quarter Section
The quarter section is created by quartering the section and thus comprises a nominal area of ​​160 acres (≈ 65 ha) with an edge length of half a mile (≈ 0.8 km). This was the standard allotment that was taken over by a settler during the American land distribution. But a homestead could also be much larger or smaller. One area for small settlers was, for example, the quarter-quarter section with 40 acres (≈ 16 ha) with an edge length of a quarter mile (≈ 0.4 km).
A survey township consists of 36 sections in a square arrangement. The target area is therefore 23,040 acres (≈ 93.2 km²) and the target area for the edge length is 6 miles (≈ 9.6 km).

Size description for agricultural goods in medieval England

Similar to the German term Hufe or Hube, the size of an agricultural property was described with corresponding terms. These dimensions are not actually measures of area, but rather served the abstract description of the entire land area of ​​a farm as a basis for taxes , lease payments or tribute payments . The decisive factor was less the actual size of the area than the yield. In the case of poor soils, the corresponding areas became larger. Below is a selection of the most popular size descriptions:

Yardland, Virgate
Approximately 30 acres in size. This was a farm that was sufficient for a full-time family.
Four times the size of a Virgate and thus around 120 acres (approx. 48 ha) in size.

Other areas

Area dimensions below one square inch
unit German Abbr. size metric size annotation
circular mil (US)
circular thou (UK) 14 • π mil 2 ≈ 0.000506707 mm 2
1000 circular mils kcmil ≈ 0.506707 mm 2 Wire cross-section, electrotechnical (USA, Canada etc.); obsolete abbreviation: MCM
square mil (US)
square thou (UK) 1 mil 2 = 0.00064516 mm²
circular inch District inch 14 • π inch² ≈ 5.06707479164 cm²
special area dimensions
unit German Abbr. size metric size annotation
square 100 feet 2 ≈ 9.3 m 2 Roofing trade, historical;
in Australia often for the footprint of houses

Volume units

Formula symbol of the volume : V

English room dimensions
unit German Abbr. size cubic meter
cubic inch Cubic inches 1 inch 3 16.4 cm 3 0.000016387064 m 3
cubic foot Cubic feet cu.ft. 1 foot 3 = 1728 inch 3 28.3 dm 3 0.028316846592 m 3
perch Manhole 1 perch ( 16 12  feet) × 1 12  feet 2 = 24 34  feet 3 701 dm 3 0.700841953 200 m 3
cubic yard Cubic yards cu.yd. 1 yard 3 = 27 feet 3 = 46656 inch 3 765 dm 3 0.764554857984 m 3
freight ton 40 feet 3 1.13 m 3 1.132673863680 m 3
load 50 feet 3 1.42 m 3 1.415842329600 m 3
register tone Register bin RT 100 feet 3 2.83 m 3 2.831684659200 m 3
acre-inch 1 acre × 1 inch = 3630 feet 3 103 m 3 102.790153129 m 3
acre-foot 1 acre × 1 foot = 43560 feet 3 1.23 dam 3 1,233.481837547 m 3

Acre-foot and acre-inch are used in agriculture and meteorology to indicate the amount of irrigation and precipitation. In the metric system, the equivalent liters per square meter and millimeter are used for this purpose (1 l / m 2 = 1 dm 3 / m 2 = 1 mm).

A perch is not only a measure of length (= pole , rod ), but (more rarely) also a measure of volume in mining.

Measure of capacity

In Great Britain, the Weights and Measures Act of 1824 , the origin of the imperial units , unified the regionally different systems of measure of measure and determined the gallon as the basic unit for both liquid and dry dimensions. The starting point for the new imperial standard gallon was the English ale gallon . The size of the new imperial gallon was determined by the volume of 10 pounds of water at 62 ° F. This is roughly equal to 277.42 cubic inches. The imperial gallon was last redefined by the Weights and Measures Act of 1985 with exactly 4.54609 liters (approx. 277.4193 cubic inches). In 1963 and re-affirmed in 1976, the corresponding Weights and Measures Act adjusted the system of measure of measure and limited it to gallon, quart, pint, gill and fluid ounce.

In the USA, the capacity systems for bulk goods and liquids are in no way related to each other. The basic unit for measuring the liquid is the originally English wine gallon with 231 cubic inches (approx. 3.79 l). This is about half a liter smaller than the English gallon. The basic unit of the American dry measure has its origins in the historical English Winchester bushel , which at the time of its abolition in England in 1824 corresponded to a cylindrical volume with a diameter of 18½ inches and a height of 8 inches. The US bushel with 2150.42 cubic inches (approx. 35.2 l) was derived from this unit, which is approx. 1.1 liters smaller than the English bushel, which has since been abolished, and in contrast to this, has no relation to the gallon stands.

Most of the English denominations of measure are also used in the American system ( drachm became dram ). You also have i. d. Usually the same factors are among each other (in the respective wet or dry measure ) (exceptions are barrel and fluid ounce ). To distinguish them, the abbreviations "Imp." Or "US" may be prefixed. It is noteworthy that the British like the US oil barrel measures around 159 liters, although one is defined as 35 and the other as 42 gallons. Furthermore, the English fluid ounce and the units of measurement below it are smaller, the units above it are larger than their respective American counterparts.

In the pharmacy system only minim, scruple, drachm, ounce, pint and gallon were used.

Attention should be paid to the sometimes confusing labeling on US beverage containers, here you will find information such as "25.4 Fluid Ounces ONE PINT 9.4 FL.OZ." or ".5L (1 PT, 0.9 FL OZ)". These mean that the content corresponds to the first item (in US wet), which in turn is the sum of the last two items (in US wet).


English measures of measure
unit German Abbr. size metric
fluid ounce Fluid ounce fl.oz., ƒ℥ 15 gill ≈ 2.84 cl = 0.0284130625 L.
gill , noggin Quarter pint gi. 14 pint ≈ 1.42 dl = 0.1420653125 L.
pint pint, pt. 12 quart ≈ 5.68 dl = 0.56826125 L.
quart quart qt. 14 gallon ≈ 1.14 l = 1.1365225 l
gallon gallon gal. 4.54609 L. ≈ 4.55 l = 4.54609 L.
Historical English liquid measures, Imperial wet
unit German Abbr. size metric
minim , drop drops min. 120 scruple 59.2 µl 0.000059193883880 L.
fluid scruple Liquid cruple, ƒ℈ 13 dram 1.18 ml 0.001183877677603 L.
fluid dram Liquid drachms fl.dr., ƒʒ 18 ounce 3.55 ml 0.003551633032809 L.
glass Glass   12 gill 7.10 cl 0.071033 L.
(petrol) barrel barrel bl., bbl. 35 gallon 1.59 hl 159.113 l
Historical English dry measurements, Imperial dry (until 1968)
unit German Abbr. size metric
peck   pk. 2 gallon 9.09 l 9,092 1 l
kenning     4 gallon 1.82 dal 18.1843 l
bushel bushel bsh., bu. 8 gallon 3.64 dal 36.3687 L.
sack, bag bag   3 bushel 1.09 hl 109.106 L.
quarter   qr. 8 bushel 2.91 hl 290.9 l
chaldron     12 sack 1.31 kl 1,309.2732 L.
load load   5 quarter 1.45 kl 1,454.5 L.
American liquid measures, US wet
unit German Abbr. size metric
minim, drop drops min. 160 dram ≈ 61.6 µl = 0.000061611519921875 L.
fluid dram Sip fl.dr., ƒʒ 18 ounce ≈ 3.70 ml = 0.0036966911953125 L.
fluid ounce Fluid ounce fl.oz., ƒ℥ 14 gill ≈ 2.96 cl = 0.0295735295625 L.
gill   gi. 14 pint ≈ 1.18 dl = 0.11829411825 L.
pint pint pt. 12 quart ≈ 4.73 dl = 0.473176473 L.
quart quart qt. 14 gallon ≈ 9.46 dl = 0.946352946 l
gallon gallon gal. 231 inch 3 ≈ 3.79 l = 3.785411784 L.
petrol barrel Oil barrel bl., bbl. 42 gallon = 12 firkin ≈ 1.59 hl = 158.987294928 l
American dry measures, US dry
unit German Abbr. size metric
(dry) pint pint pt. 12 quart ≈ 5.51 dl = 0.5506104713575 L.
(dry) quart     18 peck ≈ 1.10 l = 1.101220942715 L.
peck   pk. 14 bushel ≈ 8.81 l = 8.80976754172 L.
bushel 1 bushel bsh., bu. 2150.42 inch 3 3.52 dal = 35.23907016688 L.
1Bushel is also used as a unit of weight. See bushel (grain measure)


American volume measures for wood
unit German Abbr. size metric size annotation
cord Fathoms CD. 4 ft. × 4 ft. × 8 ft. 128 cu.ft. ≈ 3.62  stere Space for firewood
long cord 4 ft. × 4 ft. × 10 ft. 160 cu.ft. ≈ 4.53  stere
board foot BF 1 ft. × 1 ft. × 1 in. 112  cu.ft. ≈ 2.36 dm 3 Calculation measure for sawn and raw wood
1000 board feet MBF 83 13  cu.ft. ≈ 2.36 m 3 MBF is more common than BF

In the case of sawn timber , the billing measure board-foot refers to the rough- sawn and not yet dried board. The actual volume can therefore - depending on the processing status - also be lower. In the case of raw wood , the board-foot unit does not refer to the volume of the entire trunk, but to the equivalent amount of cut material that can be obtained after the cut. Rules are necessary for the calculation, the so-called log rules . Well-known log rules are the Doyle Rule and the Scribner Rule .

English volume measurements for logs
unit German Abbr. size metric size annotation
hoppus foot 4 / π cu.ft. ≈ 1.273 cu.ft. ≈ 0.0361 m 3 Calculation: (circumference [in] / 4) ² x length [ft] / 144
hoppus sound HT 50 hoppus foot ≈ 63,662 cu.ft. ≈ 1.8027 m 3

The accounting measure hoppus foot for round wood was introduced in England by Edward Hoppus in 1736 and was the predominant round wood unit in the British Empire. In the meantime, this unit is to be regarded as historical and is only rarely used in Asian tropical wood, mainly in Myanmar (Burma) in the form of the hoppus clay .

Beer and wine

Historically, there were different standardized barrel sizes for wine and beer, some with the same name ( barrel, hogshead, puncheon, butt, tun ). In addition, before 1824, beer in Great Britain made a distinction between beer and ale . As with other sizes, these room dimensions were also used like units. In particular, the (petrol) barrel , which is still in use today, developed from the tierce (159 l) - and not from one of the barrels (164 l or 119 l) . The wine measures in the UK and the USA are equivalent for all practical purposes, although they are based on the different gallons and therefore there are arithmetical differences of just under one per mille.

The German equivalents Eimer , Ohm and Oxhoft , for example, were very similar in size and definition in Prussia .

English beer containers, beer & ale / brewery from 1824
unit German Abbr. size liter
gallon gallon gal. 277.42 inch 3 4.55 l 4.54609 L.
pin code 4½ gallon = 12 firkin 2.05 dal 20.4574 L.
firkin keg 009 gallon = 12 kilderkin 4.09 dal 40.9148 L.
kilderkin 018 gallon = 12 barrel 8.18 dal 81.8296 L.
barrel (Barrel) 036 gallon 1.64 hl 163.6592 L.
hogshead hd., hhd. 054 gallon = 1 12  barrel 2.45 hl 245.489 L.
puncheon 072 gallons = 2 barrels 3.27 hl 327.3185 L.
butt 108 gallon = 2 hogshead 4.91 hl 490.978 L.
do, tone (Ton) 216 gallon = 3 puncheon = 2 butt 9.82 hl 981.9554 L.
English wine containers, imperial wine from 1824 and US
unit German Abbr. Size (UK) Size (US) Liter (UK) Liter (US)
gallon gallon gal. 277.42 inch 3 231 inch 3 4.55 l 4.54609 L. 3.79 l 3.78541 L.
rundlet bucket   015 gallon = 17 pipe 018 gallon = 17 pipe 6.82 dal 68.19135 L. 6.81 dal 68.1374 L.
barrel barrel bl. 026 14 gal. = 14 pipe 031 12 gal. = 14 pipe 1.19 hl 119.335 L. 1.19 hl 119.240 L.
tierce Ohm, third   035 gallon = 13  pipe = 12  firkin 042 gallon = 13  pipe = 12  firkin 1.59 hl 159.113 l 1.59 hl 158.987 L.
hogshead Oxhoft hd., hhd. 052 12 gal. = 14 do 063 gallon = 14 do 2.39 hl 238.670 L. 2.38 hl 238,481 L.
firkin, puncheon / pon, tertian 070 gallons = 13  do 084 gallon = 13  do 3.18 hl 318.226 L. 3.18 hl 317.975 L.
pipe, butt 105 gallon = 12  do 126 gallon = 12  do 4.77 hl 477,339 L. 4.77 hl 476,962 L.
to do (Ton) 210 gallons 252 gallons 9.55 hl 954.68 L. 9.54 hl 953.924 L.


US measuring spoon set with 18 , 14 , 12 and 1  teaspoon (TSP) as well as 12 and 1  tablespoon (TBS)

Particularly in the North American cuisine, the sizes of scoops (are spoon ) and measuring cup ( cup ) well defined, although has the appropriate containers, especially in the UK are often metric. The US version is sometimes rounded using a “metric fluid ounce” of 30 ml: 1.25 ml / ssp., 5 ml / tsp., 10 ml / dsp., 15 ml / tbsp., 180 ml / tc., 240 ml / c. They differ from the European kitchen dimensions for z. B. Teaspoon and tablespoon .

Some chefs and cookbooks use definitions other than those listed in the table, e.g. B. for the British tablespoon half a fluid ounce (14.2 ml) as is common in the American system. The names dessertspoon , saltspoon and tea cup are rare. Measuring spoons or markings of the corresponding sizes are common, but are referred to as fractions of another measure. In addition, there are usually markings for quarter , third and half cup in measuring cups .

English cooking units
unit German Abbr. Size (UK) Size (US) Liter (UK) Liter (US)
saltspoon Salt spoon ssp. 14 teaspoon 1.11 ml 0.0011098 L. 1.23 ml 0.001232230399 L.
teaspoon teaspoon tsp. 14 tablespoon 13 tablespoon 4.44 ml 0.004439 L. 4.93 ml 0.004928921595 L.
dessert spoon   dsp. 2 teaspoon 8.88 ml 0.008 879 L. 9.86 ml 0.009857843190 L.
tablespoon tablespoon tbsp. 116 cup 1.78 cl 0.017758 L. 1.48 cl 0.0147867647825 L.
tea cup Teacup tc. 13 pint 34 cup 1.89 dl 0.18942 L. 1.77 dl 0.177441177 L.
cup Cup c., cu. 12  pint = 10 ounce 12  pint = 8 ounce 2.84 dl 0.28413 L. 2.37 dl 0.2365882365 L.


Since 1979, the quantities given for (foam) wine bottles in the USA have been based on three quarters of a liter instead of one fifth of a gallon, which corresponds to a nominal reduction of around 1%. However, at the same time the larger bottles were changed more and shrank by around 25%, only shawl manasar only by around 15%.

American (foam) wine bottles
Surname German size Liter
until 1979
since 1979
gallon fifth ¾L
glass Glass 4 ounce 00.118  
split 1.6 glass 00.189 00.1875 0.05 00.25
tenth Tenth (gallon) 2 split 00.379 00.375 0.1 00.5
fifth, bottle Fifth (gallon), bottle 00.757 00.75 0.2 01
magnum Magnum 01.89 01.5 0.5 02.5 02
jeroboam Jeroboam 2 magnum 03.79 03 1 05 04th
rehoboam Rehaboam 3 magnum 05.68 04.5 1.5 07.5 06th
methuselah Methuselah 4 magnum 07.57 06th 2 10 08th
shalmanazar Shawl Manasar 10.6 09 3 14th 12
balthazar Balthazar 8 magnum 15.1 12 4th 20th 16
nebuchadnezzar Nebuchadnezzar 10 magnum 18.9 15th 5 25th 20th

Weight units

Symbol of the mass : m

Ratios of the Anglo-American weights to one another

The basic unit of the weight system, which originally came from France (around the 15th century), is the Avoirdupois pound of 7000  grains , which since July 1, 1959 has been standardized at exactly 453.59237 g of the metric system. From 1853 to 1959 this pound was defined in Great Britain by a weight of approx. 453.592338 g, while in the USA it was defined in the metric system with the Mendenhall Order as early as 1893: According to this, the Avoirdupois pound was exactly 453.5924277 g .

In the coin and precious metal industry, the Troy system is used with one pound, which weighs 5760 instead of 7000  grains , and until the 19th century (UK  Medical Act of 1858) a pharmacy system that also uses the lighter pound (Troy) at 12  ounces but used scruple and dram instead of pennyweight .

Usually the system used is determined by the context; when in doubt it is the Avoirdupois system, short in the US and long in the UK. To differentiate, short or long (seldom also net and large ) are placed before and - often abbreviated - (Avoirdupois) , (Troy) or (apothecaries) after the unit.

The units stone and hundredweight were abolished in British trade decades before the metric system was introduced; The British and Irish often give their body weight in stones and pounds and their height in feet and inches . The long (long) units resulting from the subsequent introduction of the stone to 14  pounds in the UK and were more common there than in the colonies. According to other sources that are short units the result of a partial transfer decimation of the system in North America of the 18th century, following the example of several hundredweight (centner) and quintals to 100 pounds on the European continent.

The slug is constructed as a consistent unit of mass in feet (ft) and pound-force (lb f ) in one of the English engineering systems: a mass of 1 slug is accelerated by 1 ft / s² by the force 1 lb f , where the value of Acceleration due to gravity is not standardized, cf. 1 hyl = 9.80665 kg for the technical mass unit .

English weights
unit German Abbr. size Grain Gram
grain Gran , grain gr.   0,000,0001 64.8 mg
Commercial weights , Avoirdupois
dram drachma dr. 116 ounce 0.000.0027.34375 1.77 g
ounce , coll. lid ounce oz. 116 pounds 0.000.0437.5 2.83 dag
pound lb lb., pd., #, lb m . 7000 grain 0,0007,000 4.54 hg 0,000.453,59237
short Avoirdupois
quarter Quarter penny 14 hundredweight 0.0175,000 11.3 kg 0.011,339.80925
hundredweight , cental Hundredweight cwt. 100 pounds 0.0700,000 45.4 kg 0.045,359.237
volume ton T., to., T. 20 hundredweight 14,000,000 0.907 t 0.907,184.74
long Avoirdupois
stone stone st. 14 pounds 0.0098,000 6.35 kg 0.006,350,29318
quarter Quarter penny qu., qr. l. 2 stone 0.0196,000 12.7 kg 0.012,700.58636
hundredweight Hundredweight cwt. 4 quarters 0.0784,000 50.8 kg 0.050,802.34544
volume ton T., to., T. 20 hundredweight 15,680,000 1.02 t 1,016,046.9088
Coin Weights, Troy
pennyweight Penny weight dwt. 24 grain 0.000.0024 1.56 g
ounce Troy ounce oz., tr.oz., oz.t. 20 pennyweight 0.000.0480 3.11 dag
pound Troy pound lb.,, lb.t. 12 ounce 0,0005,760 3.73 hg 0,000.373.2417216
Apothecary weights, apothecaries , until 1858
scruple Scruple s., s.ap., ℈ 20 grain 0.000.0020th 1.30 g
dram Drachma, penny dr., dr.ap., ap.dr., ʒ 3 scruple 0.000.0060 3.89 g
ounce Troy ounce oz., oz.ap., ap.oz., ℥ 8 dram = 1 troy ounce 0.000.0480 3.11 dag
pound Troy pound lb., lb.ap., 12 ounce = 1 troy pound 0,0005,760 3.73 hg 0,000.373.2417216
Engineering technology
slug 1 lb F · s 2 / ft 32.174048 lb 0.0225,218,336 14.6 kg 0.014,593.9029372


For sheep and cotton, separate weights were used in Great Britain until the 19th century. Only hundredweight and stone also exist in the normal, "long" English weight system (see above).

Wool weights
unit German Abbr. size Pound Gram
clove , nail     7 pounds 0007th 3.18 kg 0.003,175.146590
stone   st. 2 clove 0014th 6.35 kg 0.006.350.293180
death     2 stone 0028 12.7 kg 0.012,700.586360
hundredweight Hundredweight cwt. 4 death = 8 stones 0112 50.8 kg 0.050,802,345440
wey , weight 1 58 hundredweight = 13 stones 0182 82.6 kg 0.082,553.811340
bag bag 2 wey 0364 165 kg 0.165.107,622680
last, load load 12 sack 4368 1.98 t 1,981,291.472160


The bushel unit as a measure for determining a quantity of grain was originally a pure measure of volume. This unit has been an equivalent measure of mass since the 19th century. The reference point for a "bushel" is - depending on the type of grain - a certain weight that is determined at a reference moisture content and is then referred to as "standard weight / bu". Depending on the moisture content, the weight of a "bushel" grain is therefore different.

American grain gauges
unit German Abbr. Size (and humidity) Kilograms (and moisture)
bushel (corn) Bushel (corn) bu 56 pounds at 15.5% 25.401172720 kg at 15.5%
bushel (rye) Bushel (rye) bu 56 pounds at 14.0% 25.401172720 kg at 14.0%
bushel (wheat) Bushel (wheat) bu 60 pounds at 13.5% 27.215542200 kg at 13.5%
bushel (soybean) Bushel (soybeans) bu 60 pounds at 13.0% 27.215542200 kg at 13.0%


Symbol of the time : t

The only English unit of time that is often found in Great Britain these days (but rarely in the US) is fortnight (from "fourteen nights"), for example in biweekly television programs. In addition, the term fortnight is often used in Australia, where the salary and pension are usually paid every fortnight.

The other English time measures come mainly from seafaring.

English time units
unit German Abbr. size Seconds
ounce (Ounce)   112 moment   7.5 s
moment (Moment)   140 h 1.5 min 90 s
bell ( Bell )   18 watch 30 min 1800 s
watch (Guard)   4 h 240 min 14,400 s
sennight 1 week 7 days 604,800 s
fortnight 2 weeks 14 days 1,209,600 s


Formula symbol for temperature : T or θ

Thermometer (PSF) de.svg

Traditionally, in the English-speaking world, the Fahrenheit temperature scale is more common than that of Celsius . They differ in the starting point

0 ° C corresponds to 32 ° F corresponds to 273.15  K ,
0 ° F corresponds to −17 79  ° C ≈ - 17.78 ° C corresponds to 255.37 K.

and in the size of a degree (temperature difference), which, however, are in a simple linear relationship to one another:

A temperature difference of 1 ° F corresponds to 59  ° C or 59  K.

So the conversions of a temperature from Fahrenheit to Celsius and back are:

t ° C corresponds to ( 95 t + 32) ° F.
t ° F corresponds to 59 (t - 32) ° C.

Analogous to the Kelvin scale , the Rankine scale is used accordingly in science .

Derived units


Formula symbol for speed : v

English speed units
unit German Abbr. size km / h m / s
Knot node kn, nm / h 1 nm ÷ 1 h 1.852 km / h 0.5144444 m / s
Admiralty knot Knot (admiralty) kn, nm adm / h 1 sm adm ÷ 1 h 1.853184 km / h 0.514773 m / s
Mile per hour miles per hour mph, mi / h 1 mi ÷ 1 h 1.609344 km / h 0.447040 m / s
Foot per second Feet per second fps, ft / s 1 ft ÷ 1 s 1.097280 km / h 0.304800 m / s

With the international nautical mile, a knot only sinks by 1.184 m / h or 0.329 mm / s.


Symbol of force : F

Strength units
unit German Abbr. size Newton
pound-force lb lbf, lb F 1 pound g N = 196 133 ÷ 6096 lb ft / s 2 4.45 N 4.448221615260500 kg m / s 2
poundal   pdl 1 lb ft / s 2 1.38 dN 0.138254954376 kg m / s 2

Colloquially, the distinction between pound and pound-force (like kilogram to kilopond ) is often neglected, and the definition is not official. In addition, a technical pound-foot-second system was introduced in the first half of the 20th century, in which pound is the unit of force and the unit of mass is called slug . The poundal has been around since at least 1879.


Symbol of the pressure : p

Pressure units
unit German Abbr. size Pascal
Pound-force per square inch PSI psi, lb F / in 2 1 pound-force / inch 2 6.89 kPa 6894.757293168370 kg / ms 2
Pound-force per square foot lb F / ft 2 1 pound-force / foot 2 47.9 Pa 47.880258980336 kg / ms 2
Poundal per square foot pdl / ft 2 1 poundal / foot 2 1.49 Pa 1.488163943570 kg / ms 2
Torr, mmHg Torr , millimeters of mercury mmHg, mmHg 1760  atm = 101,325 / 760 Pa 1.33 hPa 133.322368 kg / ms 2
Inch mercury Inches of mercury inHg, in Hg 25.4 mm Hg 3.39 kPa 3386.388157894730 kg / ms 2


Symbol of energy or work : W or E

Energy units
unit German Abbr. size Joules
calorie (15 ° C) calorie cal, cal 15 1 g H 2 O @ 1 atm , 14.5 → 15.5 ° C 4,186 J. 4.185 5 kg m 2 / s 2
Calorie (15 ° C) Kilocalorie C, kcal 1000 calorie 4.186 kJ 4185.5 kg m 2 / s 2
British thermal unit   Btu, BTU 1 pound H 2 O.63 → 64 ° F ~ = 778 ft lb F 1.055 kJ  
therm     100,000 Btu 105.5 MJ  
quad     10,000,000,000 therm 1.055 EJ  

In addition to the 15-degree calorie, there are a few more, see Calorie . The quad means quadrillion BTU , whereby the American quadrillion is meant, i.e. 10 15  BTU.


Formula symbol for performance : P

Power units
unit German Abbr. size watt
Manpower (Manpower) 110  horsepower 7.46 daW 74.569987158227 kg m 2 / s 3
Horsepower Horsepower hp, BHP 550 lb F ft / s = 550 196 133 ÷ 6096 lb ft 2 / s 3 7.46 hW 745.699871582270 kg m 2 / s 3

The German horse power is defined as 75  kp · m / s and, at 735.49875 watts, is somewhat smaller than the British horse power ; it is sometimes called metric horsepower , so as metric horsepower referred.


Formula symbol for the torque : M

unit German Abbr. size Newton meter
Foot-pound Pound foot lb-ft, lb F ft 1 lb F x 1 ft 1.36 Nm 1.355817948331400 4 kg m 2 / s 2
Inch-pound lb-in, lb F · in 1 lb F 1 in = 112  lb-ft 1.13 dN m 0.1129848290276167 kg m 2 / s 2
Inch-ounce oz-in, oz F in 1 oz F 1 in = 1192  lb-ft 7.06 mN m 0.007061551814226 kg m 2 / s 2

Fuel consumption

Route-related fuel consumption: In the case of vehicles, the metric system of measurements indicates the amount of fuel (in liters) that is consumed per 100 km of route. In the Anglo-American system of measurement, the reverse relationship is established. This shows the distance (in miles) that can be covered with one gallon of fuel, i.e. the fuel efficiency . Since the gallon in the US Customary Units variant is smaller than in the Imperial Units (UK) variant , there are also two different sized units.

American (US) and British (UK) fuel consumption units
unit German Abbr. size Conversion factor mpg (US) Conversion factor mpg (UK)
Miles per gallon Miles per gallon mpg, MPG, mi / gal 1 mile / gallon 235.2145833  mpg (US)l / 100 km 282.4809363  mpg (UK)l / 100 km
Conversion accuracy: 1 place after the decimal point: 235  mpg (US)l / 100 km 282  mpg (UK)l / 100 km
red curve: Imperial gallon (UK), blue curve: Liquid gallon (US)

Because the metric consumption in liters per 100 kilometers - i.e. H. as SI unit without numerical factors: cl / km or dal / Mm - reciprocal to the Anglo-American efficiency specification in miles per gallon (mpg, MPG, mi / gal), the conversion factor must be divided by the original unit for the conversion into the respective target unit . The following examples should explain this:

  • 5.3 l100 km → mpg (US): 2355.3 l100 km = 44.3 mpg (US)
  • 25 mpg (US) → l100 km : 23525 mpg (US) = 9.4 l100 km

After petrol stations in Great Britain were converted to liters, but distances are still given in miles, the indication of miles per liter (mi / l) also appears there. In Canada, both l100 km and mpg (UK) are possible. The unit kilometer per liter is rarely used there, especially in the NWT . The general rule is that the consumption information is determined worldwide according to different standards and a conversion is therefore only of limited informative value (see also fuel consumption ).

Sample values
L / 100 km mi / gal (US)
2.35 100
3 78.4
3.14 75
4th 58.8
4.70 50
5 47.0
6th 39.2
7th 33.6
8th 29.4
10 23.5
11.8 20th


In the USA, at the consumer, production and retail level up to the engineering level, the illuminance is specified according to the United States customary units system using the unit foot-candle ( lumens per square foot). The unit is used in occupational safety regulations for the illumination of workplaces, paths and rooms, as well as for the illumination of streets, squares and public spaces. But it is also predominant in the field of photography and the specification of photo sensors. On the other hand, at the internationally cooperating scientific level, the SI unit Lux is predominantly used .

American (US) unit for illuminance
unit German Abbr. size Metric size
Foot-candle Foot candle (rarely used) fc, ftc, ft-c 1 fc = 1 lm / ft 2 10.76391 lx = 10.76391 lm / m 2

See also

Individual evidence

  1. Ronald Edward Zupko: Revolution in measurement: Western European weights and measures since the age of science . American Philosophical Society, 1990, ISBN 978-0-87169-186-6 , p. 261 (accessed October 13, 2012).
  2. Alanna Mitchell: America Has Two Feet. It's About to Lose One of Them. ( en ) In: New York Times . August 18, 2020. Retrieved August 19, 2020.
  3. Weights and Measures Act of 1985 (UK) Page 76: Definition of the English gallon.
  4. Weights and Measures Act of 1976 (UK) page 14: List of the valid English measures of measure.
  5. pound avoirdupois. Retrieved March 7, 2017 .

Web links

Commons : Anglo-American system of measurement  - collection of images, videos, and audio files


More specific details

  • UK laws on "Imperial Units":