An athlete who had been labeled the greatest ever female gymnast, even before she made her Olympic debut, proved that all the hype had not been misplaced as she mopped up the title by a margin of 2.100 points.
Compatriot Aly Raisman claimed silver with a total of 60.098, while Russia's Aliya Mustafina settled for bronze.
As Biles completed her final soaring tumbling pass on the floor, no one in the Rio Olympic Arena needed to wait for the judges' verdict to realize they had just seen the gold-medal winning performance.
Biles' triumph made her the fourth successive American to win the title -- following the successes of Carly Patterson, Nastia Liukin and Gabby Douglas -- which is the longest winning streak by a country in the Olympic discipline.
She also became the first woman in 20 years to win back-to-back world and Olympic all around titles.