# Claude Opus 5 vs Claude Sonnet 5.5

As of Oct 15, 2026, Claude Opus 5 leads Claude Sonnet 5.5 in 4 of 9 shared categories: General LLM, Reasoning, Long context, and Factuality.

Claude Opus 5: $10 per 1M blended tokens.

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

Claude Opus 5: closed weights.

Claude Sonnet 5.5: closed weights.

- Which to pick, General LLM: As of Oct 15, 2026, Claude Opus 5 leads Claude Sonnet 5.5 in General LLM at #11 against #29.
- Which to pick, Reasoning: As of Oct 15, 2026, Claude Opus 5 leads Claude Sonnet 5.5 in Reasoning at #9 against #18.
- Which to pick, Science: As of Oct 15, 2026, Claude Sonnet 5.5 leads Claude Opus 5 in Science at #3 against #12.
- Which to pick, Coding: As of Oct 15, 2026, Claude Sonnet 5.5 leads Claude Opus 5 in Coding at #1 against #4.
- Which to pick, Coding › Agentic: As of Oct 15, 2026, Claude Sonnet 5.5 leads Claude Opus 5 in Coding › Agentic at #1 against #4.
- Which to pick, Coding › Web dev: As of Oct 15, 2026, Claude Sonnet 5.5 leads Claude Opus 5 in Coding › Web dev at #3 against #6.
- Which to pick, Long context: As of Oct 15, 2026, Claude Opus 5 leads Claude Sonnet 5.5 in Long context at #9 against #11.
- Which to pick, Vision: As of Oct 15, 2026, Claude Sonnet 5.5 leads Claude Opus 5 in Vision at #1 against #12.
- Which to pick, Factuality: As of Oct 15, 2026, Claude Opus 5 leads Claude Sonnet 5.5 in Factuality at #4 against #17.

As of Oct 15, 2026, Claude Opus 5 is near state of the art, rank #4 in Factuality (since Oct 15, 2026; sources LMArena Text factuality; 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).