The 22-year-old's fourth gold medal of the week in Stuttgart, in the balance beam final, ensures she has now overtaken Belarusian Vitaly Scherbo's tally of 23.
Four-time Olympic champion Biles now holds 18 gold medals across four championships against 12 for Scherbo, who competed in five world events between 1991 and 1996.
Inside a packed arena in Stuttgart, Biles delivered a polished routine on the beam before a full twisting double tuck dismount for a score of 15.066.
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