John Isner holds a solid career record of 489–317 across 806 matches (60.7%). A winning majority across 806 matches shows consistent ability to get results on Tour. With 16 titles, among the most prolific champions in the Open Era: Auckland, Newport, Winston-Salem, Houston and 2 more.
At Grand Slam level (Australian Open, Roland Garros, Wimbledon, US Open): a positive 87–58 (60.0%) across 145 matches — a player who generally rises to the occasion at the Slams.
ATP Masters 1000 (Indian Wells, Miami, Monte Carlo, Madrid, Rome, Canada, Cincinnati, Shanghai, Paris): a positive 145–96 (60.2%) across 241 matches — winning above .500 at this level, week in week out, is a genuine sign of quality.
31 finals reached — won 16, lost 15 (solid 52% conversion) — consistently getting to finals and winning the majority is a hallmark of elite performers. 62 semifinals. 102 quarterfinals.
vs. Top 10: 29–80 (26.6%, 109 matches). Top 10 opponents have represented a clear ceiling; addressing that deficit is the single biggest lever for improving the overall record.
By format — best-of-five: 98–69 (58.7%); best-of-three: 391–248 (61.2%). Slightly stronger in three-set contests, though the five-set record is still respectable.
Dominant season: 2012 — 45–21 (68.2%) from 66 matches. That year represents a level of dominance that sets the ceiling for what John Isner can produce.
