Claude Fable 5.1 vs Claude Sonnet 5.5
As of Oct 14, 2026, Claude Fable 5.1 leads Claude Sonnet 5.5 in 5 of 9 shared categories: General LLM, Reasoning, Math, Long context, and Factuality.
Claude Fable 5.1
Yes. SOTA in co-SOTA in Factuality.
Claude Sonnet 5.5
Yes. SOTA in co-SOTA in Coding, co-SOTA in Coding › Agentic and co-SOTA in Vision.
| Category | Claude Fable 5.1 | Claude Sonnet 5.5 |
|---|---|---|
| General LLM | #6 · Was SOTA · General LLM Margin 4.08163265306122 LMArena leaderboard dataset · Oct 13, 2026 | #27 · #27 in General LLM Margin 18.367346938775512 LMArena leaderboard dataset · Oct 13, 2026 |
| Reasoning | #5 · Was SOTA · Reasoning Margin 4.109589041095887 LMArena leaderboard dataset · Oct 13, 2026 | #18 · #18 in Reasoning Margin 13.013698630136986 LMArena leaderboard dataset · Oct 13, 2026 |
| Math | #2 · Near-SOTA · Math Margin 2.2222222222222285 Epoch AI benchmarking hub · Sep 1, 2026 | #4 · #4 in Math Margin 6.666666666666671 Epoch AI benchmarking hub · Sep 28, 2026 |
| Science | — | #3 · #3 in Science Margin — Epoch AI benchmarking hub · Sep 28, 2026 |
| Coding | #3 · Near-SOTA · Coding Margin 18.181818181818187 Terminal-Bench Harbor Hub · Oct 6, 2026 | #1 · Co-SOTA · Coding Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 |
| Coding › Agentic | #3 · Near-SOTA · Coding › Agentic Margin 18.181818181818187 Terminal-Bench Harbor Hub · Oct 6, 2026 | #1 · Co-SOTA · Coding › Agentic Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 |
| Coding › Web dev | #5 · Near-SOTA · Coding › Web dev Margin 3.738317757009341 LMArena leaderboard dataset · Oct 13, 2026 | #3 · Near-SOTA · Coding › Web dev Margin 1.8691588785046775 LMArena leaderboard dataset · Oct 13, 2026 |
| Long context | #6 · Was SOTA · Long context Margin 4.08163265306122 LMArena leaderboard dataset · Oct 13, 2026 | #11 · #11 in Long context Margin 7.482993197278915 LMArena leaderboard dataset · Oct 13, 2026 |
| Vision | #6 · #6 in Vision Margin 18.421052631578945 Epoch AI benchmarking hub · Sep 1, 2026 | #1 · Co-SOTA · Vision Margin 0 Epoch AI benchmarking hub · Sep 28, 2026 |
| Factuality | #1 · Co-SOTA · Factuality Margin 0 LMArena leaderboard dataset · Oct 13, 2026 | #16 · #16 in Factuality Margin 12.68656716417911 LMArena leaderboard dataset · Oct 13, 2026 |
| Abstraction (ARC) | #3 · #3 in Abstraction (ARC) Margin — Epoch AI benchmarking hub · Sep 1, 2026 | — |
Claude Fable 5.1: $20 per 1M blended tokens.
Claude Sonnet 5.5: $4.000000000000001 per 1M blended tokens.
Claude Fable 5.1: closed weights.
Claude Sonnet 5.5: closed weights.
General LLM: As of Oct 14, 2026, Claude Fable 5.1 leads Claude Sonnet 5.5 in General LLM at #6 against #27.
Reasoning: As of Oct 14, 2026, Claude Fable 5.1 leads Claude Sonnet 5.5 in Reasoning at #5 against #18.
Math: As of Oct 14, 2026, Claude Fable 5.1 leads Claude Sonnet 5.5 in Math at #2 against #4.
Coding: As of Oct 14, 2026, Claude Sonnet 5.5 leads Claude Fable 5.1 in Coding at #1 against #3.
Coding › Agentic: As of Oct 14, 2026, Claude Sonnet 5.5 leads Claude Fable 5.1 in Coding › Agentic at #1 against #3.
Coding › Web dev: As of Oct 14, 2026, Claude Sonnet 5.5 leads Claude Fable 5.1 in Coding › Web dev at #3 against #5.
Long context: As of Oct 14, 2026, Claude Fable 5.1 leads Claude Sonnet 5.5 in Long context at #6 against #11.
Vision: As of Oct 14, 2026, Claude Sonnet 5.5 leads Claude Fable 5.1 in Vision at #1 against #6.
Factuality: As of Oct 14, 2026, Claude Fable 5.1 leads Claude Sonnet 5.5 in Factuality at #1 against #16.
Claude Fable 5.1 · Claude Sonnet 5.5
Claude Fable 5.1 or Claude Sonnet 5.5?
As of Oct 14, 2026, Claude Fable 5.1 leads Claude Sonnet 5.5 in 5 of 9 shared categories: General LLM, Reasoning, Math, Long context, and Factuality.
Claude Fable 5.1 or Claude Sonnet 5.5 for General LLM?
As of Oct 14, 2026, Claude Fable 5.1 leads Claude Sonnet 5.5 in General LLM at #6 against #27.
Claude Fable 5.1 or Claude Sonnet 5.5 for Reasoning?
As of Oct 14, 2026, Claude Fable 5.1 leads Claude Sonnet 5.5 in Reasoning at #5 against #18.
Claude Fable 5.1 or Claude Sonnet 5.5 for Math?
As of Oct 14, 2026, Claude Fable 5.1 leads Claude Sonnet 5.5 in Math at #2 against #4.