# Claude Opus 4.5 vs Claude Opus 5.5

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

Claude Opus 4.5: $10 per 1M blended tokens.

Claude Opus 5.5: $8.000000000000002 per 1M blended tokens.

Claude Opus 4.5: closed weights.

Claude Opus 5.5: closed weights.

- Which to pick, General LLM: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in General LLM at #2 against #41.
- Which to pick, Reasoning: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Reasoning at #1 against #30.
- Which to pick, Science: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Science at #31 against #68.
- Which to pick, Coding › Web dev: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Coding › Web dev at #1 against #58.
- Which to pick, Long context: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Long context at #1 against #20.
- Which to pick, Factuality: As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Factuality at #1 against #40.
- Which to pick, Abstraction (ARC): As of Oct 15, 2026, Claude Opus 5.5 leads Claude Opus 4.5 in Abstraction (ARC) at #1 against #49.

As of Oct 15, 2026, Claude Opus 4.5 is a former state-of-the-art holder in Reasoning (since Dec 1, 2025; sources LMArena Text (style-controlled, hard prompts); methodology v1.0).

As of Oct 15, 2026, Claude Opus 5.5 is tied for state of the art in Reasoning (since Oct 2, 2026; sources LMArena Text (style-controlled, hard prompts); methodology v1.0).