Dekker completed her first European Cup race in Adelboden in January 2012 and finished 23rd in the parallel giant slalom. At the Snowboard Junior World Championships 2012 in Sierra Nevada , she achieved 22nd place in the parallel giant slalom and 16th place in the parallel slalom. In December 2012 she made her debut in Carezza in the Snowboard World Cup and finished 42nd in the parallel giant slalom. At the European Olympic Winter Youth Festival 2013 in Predeal , she won the bronze medal in the parallel giant slalom. At the Snowboard Junior World Championships 2013 in Erzurum she came in 12th place in the parallel slalom and in the parallel giant slalom. The following year she achieved her first top ten placement in the World Cup with tenth place in the parallel slalom in Bad Gastein . At the 2014 Winter Olympics in Sochi , she won 22nd place in the parallel giant slalom and 19th place in the parallel slalom. In March 2014 she won the silver medal in the parallel slalom at the 2014 Junior Snowboarding World Championships in Chiesa in Valmalenco . In addition, she achieved seventh place in the parallel giant slalom. After becoming the Dutch champion in parallel slalom at the beginning of the 2014/15 season, she came 25th in the parallel giant slalom and 23rd in the parallel slalom at the 2015 Snowboard World Championships on Kreischberg . In February 2015 she finished second three times and third once in the European Cup, and at the end of the season she reached fourth place in the parallel ranking. At the 2015 Snowboard Junior World Championships in Yabuli , she won the silver medal in the parallel giant slalom. At the beginning of the 2016/17 season, she won her first European Cup victory in the parallel slalom in Landgraaf . In January 2017 she reached her first podium in the World Cup with second place in the parallel slalom in Bad Gastein. At the season highlight of the 2017 Snowboard World Championships in Sierra Nevada , she finished 19th in the parallel slalom and in the parallel giant slalom. At the end of the season she finished fourth in the Parallel Slalom World Cup. In the 2017/18 season she came with two top ten placements, including third place in the parallel slalom in Bad Gastein and ninth place in the parallel slalom World Cup. At the 2018 Winter Olympics in Pyeongchang , she finished 17th in the parallel giant slalom. The following year she went to the World Championships in Park City to 21st place in the parallel slalom and 12th place in the parallel giant slalom.
Dekker has participated in 50 world cup races so far. She achieved a top ten placement nine times (as of the end of the 2019/20 season).
Netherlands
World cup
