Up to four models

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Side by side on the same independent tests, with price and context. The link in your address bar shares this exact comparison.

Claude Opus 5.5Kimi K3

Next to Claude Opus 5.5

Presets

Claude Opus 5.5

200188–211

WeightsClosed

ReleasedSep 2026

Price in / out$4.0 / $20

Context1M

Core tests taken4 of 8

Kimi K3

172161–183

WeightsOpen

ReleasedJul 2026

Price in / out$0.68 / $10

Context1.05M

Core tests taken4 of 8

Claude Opus 5.5 leads Kimi K3 by 27 points, ahead on 3 of 4 shared core tests, at 2.7× the price.

Test by testindependent results · Epoch AI

Claude Opus 5.5Kimi K3

Only tests that at least two of these models have taken. Bold rows are the core tests shown on every profile; all of these results inform the index score. Task length (METR) is listed below the chart because it is a duration, not a percentage.