Head-to-head comparison across 3benchmark categories. Overall scores shown here use BenchLM's provisional ranking lane.
Claude Sonnet 5
94
Kimi K2.5
63
Verified leaderboard positions: Claude Sonnet 5 unranked · Kimi K2.5 #18
Pick Claude Sonnet 5 if you want the stronger benchmark profile. Kimi K2.5 only becomes the better choice if knowledge is the priority or you want the cheaper token bill.
Agentic
+27.2 difference
Coding
+1.0 difference
Knowledge
+7.7 difference
Claude Sonnet 5
Kimi K2.5
$3 / $15
$0.6 / $3
N/A
45 t/s
N/A
2.38s
1M
256K
Pick Claude Sonnet 5 if you want the stronger benchmark profile. Kimi K2.5 only becomes the better choice if knowledge is the priority or you want the cheaper token bill.
Claude Sonnet 5 is clearly ahead on the provisional aggregate, 94 to 63. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Sonnet 5's sharpest advantage is in agentic, where it averages 81.8 against 54.6. The single biggest benchmark swing on the page is Terminal-Bench 2.0, 80.4% to 50.8%. Kimi K2.5 does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.
Claude Sonnet 5 is also the more expensive model on tokens at $3.00 input / $15.00 output per 1M tokens, versus $0.60 input / $3.00 output per 1M tokens for Kimi K2.5. That is roughly 5.0x on output cost alone. Claude Sonnet 5 is the reasoning model in the pair, while Kimi K2.5 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 Sonnet 5 gives you the larger context window at 1M, compared with 256K for Kimi K2.5.
Claude Sonnet 5 is ahead on BenchLM's provisional leaderboard, 94 to 63. The biggest single separator in this matchup is Terminal-Bench 2.0, where the scores are 80.4% and 50.8%.
Kimi K2.5 has the edge for knowledge tasks in this comparison, averaging 65.1 versus 57.4. Inside this category, HLE is the benchmark that creates the most daylight between them.
Kimi K2.5 has the edge for coding in this comparison, averaging 64.2 versus 63.2. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.
Claude Sonnet 5 has the edge for agentic tasks in this comparison, averaging 81.8 versus 54.6. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.
Estimates at 50,000 req/day · 1000 tokens/req average.
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