Claude Opus 5.5 vs Claude Sonnet 5.5
As of Oct 14, 2026, Claude Opus 5.5 leads Claude Sonnet 5.5 in 5 of 9 shared categories: General LLM, Reasoning, Coding › Web dev, Long context, and Factuality.
Claude Opus 5.5
Yes. SOTA in co-SOTA in Reasoning, co-SOTA in Coding, co-SOTA in Coding › Agentic, Coding › Web dev, co-SOTA in Long context and 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 Opus 5.5 | Claude Sonnet 5.5 |
|---|---|---|
| General LLM | #2 · Near-SOTA · General LLM Margin 1.3605442176870781 LMArena leaderboard dataset · Oct 13, 2026 | #27 · #27 in General LLM Margin 18.367346938775512 LMArena leaderboard dataset · Oct 13, 2026 |
| Reasoning | #1 · Co-SOTA · Reasoning Margin 0 LMArena leaderboard dataset · Oct 13, 2026 | #18 · #18 in Reasoning Margin 13.013698630136986 LMArena leaderboard dataset · Oct 13, 2026 |
| Math | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 2026 | #4 · #4 in Math Margin 6.666666666666671 Epoch AI benchmarking hub · Sep 28, 2026 |
| Science | #31 · #31 in Science Margin — Epoch AI benchmarking hub · Sep 22, 2026 | #3 · #3 in Science Margin — Epoch AI benchmarking hub · Sep 28, 2026 |
| Coding | #1 · Co-SOTA · Coding Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 | #1 · Co-SOTA · Coding Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 |
| Coding › Agentic | #1 · Co-SOTA · Coding › Agentic Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 | #1 · Co-SOTA · Coding › Agentic Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 |
| Coding › Web dev | #1 · SOTA · Coding › Web dev Margin 0 LMArena leaderboard dataset · Oct 13, 2026 | #3 · Near-SOTA · Coding › Web dev Margin 1.8691588785046775 LMArena leaderboard dataset · Oct 13, 2026 |
| Long context | #1 · Co-SOTA · Long context Margin 0 LMArena leaderboard dataset · Oct 13, 2026 | #11 · #11 in Long context Margin 7.482993197278915 LMArena leaderboard dataset · Oct 13, 2026 |
| Vision | #4 · Near-SOTA · Vision Margin 13.15789473684211 Epoch AI benchmarking hub · Sep 22, 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) | #1 · #1 in Abstraction (ARC) Margin — Epoch AI benchmarking hub · Sep 22, 2026 | — |
Claude Opus 5.5: $8.000000000000002 per 1M blended tokens.
Claude Sonnet 5.5: $4.000000000000001 per 1M blended tokens.
Claude Opus 5.5: closed weights.
Claude Sonnet 5.5: closed weights.
General LLM: As of Oct 14, 2026, Claude Opus 5.5 leads Claude Sonnet 5.5 in General LLM at #2 against #27.
Reasoning: As of Oct 14, 2026, Claude Opus 5.5 leads Claude Sonnet 5.5 in Reasoning at #1 against #18.
Science: As of Oct 14, 2026, Claude Sonnet 5.5 leads Claude Opus 5.5 in Science at #3 against #31.
Coding: As of Oct 14, 2026, Claude Opus 5.5 and Claude Sonnet 5.5 share #1 in Coding.
Coding › Agentic: As of Oct 14, 2026, Claude Opus 5.5 and Claude Sonnet 5.5 share #1 in Coding › Agentic.
Coding › Web dev: As of Oct 14, 2026, Claude Opus 5.5 leads Claude Sonnet 5.5 in Coding › Web dev at #1 against #3.
Long context: As of Oct 14, 2026, Claude Opus 5.5 leads Claude Sonnet 5.5 in Long context at #1 against #11.
Vision: As of Oct 14, 2026, Claude Sonnet 5.5 leads Claude Opus 5.5 in Vision at #1 against #4.
Factuality: As of Oct 14, 2026, Claude Opus 5.5 leads Claude Sonnet 5.5 in Factuality at #1 against #16.
Claude Opus 5.5 · Claude Sonnet 5.5
Claude Opus 5.5 or Claude Sonnet 5.5?
As of Oct 14, 2026, Claude Opus 5.5 leads Claude Sonnet 5.5 in 5 of 9 shared categories: General LLM, Reasoning, Coding › Web dev, Long context, and Factuality.
Claude Opus 5.5 or Claude Sonnet 5.5 for General LLM?
As of Oct 14, 2026, Claude Opus 5.5 leads Claude Sonnet 5.5 in General LLM at #2 against #27.
Claude Opus 5.5 or Claude Sonnet 5.5 for Reasoning?
As of Oct 14, 2026, Claude Opus 5.5 leads Claude Sonnet 5.5 in Reasoning at #1 against #18.
Claude Opus 5.5 or Claude Sonnet 5.5 for Science?
As of Oct 14, 2026, Claude Sonnet 5.5 leads Claude Opus 5.5 in Science at #3 against #31.