Side-by-side benchmark comparison across knowledge, coding, math, and reasoning.
Claude Opus 4.5 is clearly ahead on the aggregate, 85 to 56. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Opus 4.5's sharpest advantage is in coding, where it averages 72 against 49.3. The single biggest benchmark swing on the page is GPQA, 97 to 77.2. o3-mini does hit back in instruction following, so the answer changes if that is the part of the workload you care about most.
o3-mini is the reasoning model in the pair, while Claude Opus 4.5 is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use.
Pick Claude Opus 4.5 if you want the stronger benchmark profile. o3-mini only becomes the better choice if instruction following is the priority or you want the stronger reasoning-first profile.
Claude Opus 4.5
80.8
o3-mini
82.1
Claude Opus 4.5
72
o3-mini
49.3
Claude Opus 4.5
96.1
o3-mini
87.3
Claude Opus 4.5
90
o3-mini
93.9
Claude Opus 4.5 is ahead overall, 85 to 56. The biggest single separator in this matchup is GPQA, where the scores are 97 and 77.2.
o3-mini has the edge for knowledge tasks in this comparison, averaging 82.1 versus 80.8. Inside this category, GPQA is the benchmark that creates the most daylight between them.
Claude Opus 4.5 has the edge for coding in this comparison, averaging 72 versus 49.3. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.
Claude Opus 4.5 has the edge for math in this comparison, averaging 96.1 versus 87.3. Inside this category, AIME 2024 is the benchmark that creates the most daylight between them.
o3-mini has the edge for instruction following in this comparison, averaging 93.9 versus 90. Inside this category, IFEval is the benchmark that creates the most daylight between them.
Get notified when new models drop, benchmark scores change, or the leaderboard shifts. One email per week.
Free. No spam. Unsubscribe anytime. We only store derived location metadata for consent routing.