# Claude Opus 4.6 vs Claude Sonnet 5.5

As of Oct 15, 2026, Claude Opus 4.6 leads Claude Sonnet 5.5 in 4 of 7 shared categories: General LLM, Reasoning, Long context, and Factuality.

Claude Opus 4.6: $10 per 1M blended tokens.

Claude Sonnet 5.5: $4.000000000000001 per 1M blended tokens.

Claude Opus 4.6: closed weights.

Claude Sonnet 5.5: closed weights.

- Which to pick, General LLM: As of Oct 15, 2026, Claude Opus 4.6 leads Claude Sonnet 5.5 in General LLM at #4 against #29.
- Which to pick, Reasoning: As of Oct 15, 2026, Claude Opus 4.6 leads Claude Sonnet 5.5 in Reasoning at #2 against #18.
- Which to pick, Math: As of Oct 15, 2026, Claude Sonnet 5.5 leads Claude Opus 4.6 in Math at #4 against #11.
- Which to pick, Science: As of Oct 15, 2026, Claude Sonnet 5.5 leads Claude Opus 4.6 in Science at #3 against #32.
- Which to pick, Coding › Web dev: As of Oct 15, 2026, Claude Sonnet 5.5 leads Claude Opus 4.6 in Coding › Web dev at #3 against #37.
- Which to pick, Long context: As of Oct 15, 2026, Claude Opus 4.6 leads Claude Sonnet 5.5 in Long context at #2 against #11.
- Which to pick, Factuality: As of Oct 15, 2026, Claude Opus 4.6 leads Claude Sonnet 5.5 in Factuality at #3 against #17.

As of Oct 15, 2026, Claude Opus 4.6 is near state of the art, rank #2 in Reasoning (since Oct 15, 2026; sources LMArena Text (style-controlled, hard prompts); methodology v1.0).

As of Oct 15, 2026, Claude Sonnet 5.5 is tied for state of the art in Coding (since Oct 6, 2026; sources Terminal-Bench 4.0; methodology v1.0).