Maker attended the 2016 NBA Draft Combine, where he was measured as the third-tallest player without shoes at and recorded the highest no-step vertical jump (32") of any player over in NBA Draft Combine history. In the days leading up to the draft, a number of teams ruled themselves out of selecting Maker in the first round over concerns that his age had been misrepresented, as some believed Maker to be between 21–23 years of age despite being officially listed as a 19-year-old. Despite those concerns, he was selected with the 10th overall pick in the 2016 draft by the Milwaukee Bucks, becoming the first high school player taken in the first round since the 2005 Collective Bargaining Agreement went into effect.