Up to four models

Compare

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

Claude Opus 5.5GPT-6.1 Sol

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

GPT-6.1 Sol

184168–200

WeightsClosed

ReleasedSep 2026

Price in / out$2.0 / $10

Context1.05M

Core tests taken3 of 8

Claude Opus 5.5 leads GPT-6.1 Sol by 16 points, ahead on 1 of 3 shared core tests, at 2.0× the price.

Test by testindependent results · Epoch AI

Claude Opus 5.5GPT-6.1 Sol

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.