Miss Dekker, who is 16 years and four months old, has cut six months off the unofficial record set in 2010 by Australian teenager Jessica Watson, who was days away from her 17th birthday when she completed her own non-stop voyage.
Dozens of people jumped and cheered as Miss Dekker stepped aboard a dock in St. Maarten and waved.
“There were moments where I was like, ‘What the hell am I doing out here?,’ but I never wanted to stop,” she told reporters.
“It’s a dream, and I wanted to do it.”