The daughter of a building contractor has been playing in the Schwarz-Weiß tennis club in Essen since 1925 and switched to the ETuF in Essen in 1927 . In 1929 she became Hungarian champion in singles and German champion in singles and doubles. In 1931 she was defeated by Cilly Aussem in the only all-German Wimbledon final to date . In 1933 Krahwinkel won the Wimbledon mixed title with Gottfried von Cramm , in the same year she married the Dane Sven Sperling and took on Danish citizenship.
From 1935 to 1937 she was successful three times at the French International Championships. Here she always defeated Simonne Mathieu in the final . In the history of the French Open , only Helen Wills Moody (1928–1930), Monica Seles (1990–1992) and Justine Henin (2005–2007) succeeded in such a hat trick . In 1936 she moved back to the individual finals at Wimbledon, but lost to the American Helen Jacobs . She also won the international German tennis championships six times in a row from 1933 to 1939.
In her career, which lasted until 1952, she won 123 titles in 16 countries and was one of the most successful players in the world during that time. She died in 1981 at the age of 72 in her adopted home Sweden .