Head-to-head comparison across 4benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
Claude Opus 4.5
80
Kimi K2.5 (Reasoning)
79
Verified leaderboard positions: Claude Opus 4.5 #7 · Kimi K2.5 (Reasoning) unranked
Pick Claude Opus 4.5 if you want the stronger benchmark profile. Kimi K2.5 (Reasoning) only becomes the better choice if knowledge is the priority or you want the stronger reasoning-first profile.
Agentic
+7.9 difference
Coding
+10.9 difference
Knowledge
+21.1 difference
Multimodal
+7.9 difference
Claude Opus 4.5
Kimi K2.5 (Reasoning)
$null / $null
$null / $null
46 t/s
N/A
1.01s
N/A
200K
128K
Pick Claude Opus 4.5 if you want the stronger benchmark profile. Kimi K2.5 (Reasoning) only becomes the better choice if knowledge is the priority or you want the stronger reasoning-first profile.
Claude Opus 4.5 finishes one point ahead on BenchLM's provisional leaderboard, 80 to 79. That is enough to call, but not enough to treat as a blowout. This matchup comes down to a few meaningful edges rather than one model dominating the board.
Claude Opus 4.5's sharpest advantage is in agentic, where it averages 62.5 against 54.6. The single biggest benchmark swing on the page is Terminal-Bench 2.0, 59.3% to 50.8%. Kimi K2.5 (Reasoning) does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.
Kimi K2.5 (Reasoning) 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. Claude Opus 4.5 gives you the larger context window at 200K, compared with 128K for Kimi K2.5 (Reasoning).
Claude Opus 4.5 is ahead on BenchLM's provisional leaderboard, 80 to 79. The biggest single separator in this matchup is Terminal-Bench 2.0, where the scores are 59.3% and 50.8%.
Kimi K2.5 (Reasoning) has the edge for knowledge tasks in this comparison, averaging 87.3 versus 66.2. Inside this category, MMLU-Pro is the benchmark that creates the most daylight between them.
Kimi K2.5 (Reasoning) has the edge for coding in this comparison, averaging 76.8 versus 65.9. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.
Claude Opus 4.5 has the edge for agentic tasks in this comparison, averaging 62.5 versus 54.6. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.
Kimi K2.5 (Reasoning) has the edge for multimodal and grounded tasks in this comparison, averaging 78.5 versus 70.6. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.
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