# Claude Fable 5.1 vs Claude Opus 4.1

As of Oct 15, 2026, Claude Fable 5.1 leads Claude Opus 4.1 in 6 of 6 shared categories: General LLM, Reasoning, Math, Coding › Web dev, Long context, and Factuality.

Claude Fable 5.1: $20 per 1M blended tokens.

Claude Opus 4.1: $29.999999999999996 per 1M blended tokens.

Claude Fable 5.1: closed weights.

Claude Opus 4.1: closed weights.

- Which to pick, General LLM: As of Oct 15, 2026, Claude Fable 5.1 leads Claude Opus 4.1 in General LLM at #6 against #73.
- Which to pick, Reasoning: As of Oct 15, 2026, Claude Fable 5.1 leads Claude Opus 4.1 in Reasoning at #5 against #60.
- Which to pick, Math: As of Oct 15, 2026, Claude Fable 5.1 leads Claude Opus 4.1 in Math at #2 against #27.
- Which to pick, Coding › Web dev: As of Oct 15, 2026, Claude Fable 5.1 leads Claude Opus 4.1 in Coding › Web dev at #5 against #84.
- Which to pick, Long context: As of Oct 15, 2026, Claude Fable 5.1 leads Claude Opus 4.1 in Long context at #6 against #52.
- Which to pick, Factuality: As of Oct 15, 2026, Claude Fable 5.1 leads Claude Opus 4.1 in Factuality at #1 against #93.

As of Oct 15, 2026, Claude Fable 5.1 is tied for state of the art in Factuality (since Oct 2, 2026; sources LMArena Text factuality; methodology v1.0).

As of Oct 15, 2026, Claude Opus 4.1 is a former state-of-the-art holder in General LLM (since Aug 18, 2025; sources LMArena Text (style-controlled, overall); methodology v1.0).