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Claude Opus 5.5Step 5 Preview

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

Step 5 Preview

~175estimated

WeightsClosed

ReleasedSep 2026

Price in / out–

Context–

Core tests taken–

Claude Opus 5.5 leads Step 5 Preview by 25 points (one score is an estimate).

Test by testindependent results · Epoch AI

Claude Opus 5.5Step 5 Preview

These models share no independent tests yet.

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.