# Claude Sonnet 4.5 vs GPT-5.5

As of Oct 15, 2026, Claude Sonnet 4.5 leads GPT-5.5 in 0 of 7 shared categories.

Claude Sonnet 4.5: $6 per 1M blended tokens.

GPT-5.5: $11.25 per 1M blended tokens.

Claude Sonnet 4.5: closed weights.

GPT-5.5: closed weights.

- Which to pick, General LLM: As of Oct 15, 2026, GPT-5.5 leads Claude Sonnet 4.5 in General LLM at #22 against #62.
- Which to pick, Reasoning: As of Oct 15, 2026, GPT-5.5 leads Claude Sonnet 4.5 in Reasoning at #26 against #51.
- Which to pick, Science: As of Oct 15, 2026, GPT-5.5 leads Claude Sonnet 4.5 in Science at #30 against #82.
- Which to pick, Coding › Web dev: As of Oct 15, 2026, GPT-5.5 leads Claude Sonnet 4.5 in Coding › Web dev at #48 against #86.
- Which to pick, Long context: As of Oct 15, 2026, GPT-5.5 leads Claude Sonnet 4.5 in Long context at #26 against #34.
- Which to pick, Factuality: As of Oct 15, 2026, GPT-5.5 leads Claude Sonnet 4.5 in Factuality at #5 against #61.
- Which to pick, Abstraction (ARC): As of Oct 15, 2026, GPT-5.5 leads Claude Sonnet 4.5 in Abstraction (ARC) at #7 against #66.

As of Oct 15, 2026, Claude Sonnet 4.5 is a former state-of-the-art holder in General LLM (since Oct 3, 2025; sources LMArena Text (style-controlled, overall); methodology v1.0).

As of Oct 15, 2026, GPT-5.5 is near state of the art, rank #5 in Factuality (since Oct 15, 2026; sources LMArena Text factuality; methodology v1.0).