Claude 3.5 Sonnet vs Claude Opus 5.5
As of Oct 14, 2026, Claude 3.5 Sonnet leads Claude Opus 5.5 in 0 of 4 shared categories.
Claude 3.5 Sonnet
It used to be. Was SOTA in General LLM.
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.
| Category | Claude 3.5 Sonnet | Claude Opus 5.5 |
|---|---|---|
| General LLM | #140 · Was SOTA · General LLM Margin 95.23809523809524 LMArena leaderboard dataset · Oct 13, 2026 | #2 · Near-SOTA · General LLM Margin 1.3605442176870781 LMArena leaderboard dataset · Oct 13, 2026 |
| Reasoning | #136 · Was SOTA · Reasoning Margin 93.83561643835617 LMArena leaderboard dataset · Oct 13, 2026 | #1 · Co-SOTA · Reasoning Margin 0 LMArena leaderboard dataset · Oct 13, 2026 |
| Math | #43 · #43 in Math Margin 95.55555555555556 Epoch AI benchmarking hub · Oct 22, 2024 | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 2026 |
| Science | #119 · #119 in Science Margin — Epoch AI benchmarking hub · Oct 22, 2024 | #31 · #31 in Science Margin — Epoch AI benchmarking hub · Sep 22, 2026 |
| Coding | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 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 |
| Coding › Web dev | — | #1 · SOTA · Coding › Web dev Margin 0 LMArena leaderboard dataset · Oct 13, 2026 |
| Long context | #126 · Was SOTA · Long context Margin 85.71428571428571 LMArena leaderboard dataset · Oct 13, 2026 | #1 · Co-SOTA · Long context Margin 0 LMArena leaderboard dataset · Oct 13, 2026 |
| Vision | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 9, 2026 | #4 · Near-SOTA · Vision Margin 13.15789473684211 Epoch AI benchmarking hub · Sep 22, 2026 |
| Factuality | — | #1 · Co-SOTA · Factuality Margin 0 LMArena leaderboard dataset · Oct 13, 2026 |
| Abstraction (ARC) | — | #1 · #1 in Abstraction (ARC) Margin — Epoch AI benchmarking hub · Sep 22, 2026 |
Claude 3.5 Sonnet: price per 1M tokens is unset in the catalog.
Claude Opus 5.5: $8.000000000000002 per 1M blended tokens.
Claude 3.5 Sonnet: closed weights.
Claude Opus 5.5: closed weights.
General LLM: As of Oct 14, 2026, Claude Opus 5.5 leads Claude 3.5 Sonnet in General LLM at #2 against #140.
Reasoning: As of Oct 14, 2026, Claude Opus 5.5 leads Claude 3.5 Sonnet in Reasoning at #1 against #136.
Science: As of Oct 14, 2026, Claude Opus 5.5 leads Claude 3.5 Sonnet in Science at #31 against #119.
Long context: As of Oct 14, 2026, Claude Opus 5.5 leads Claude 3.5 Sonnet in Long context at #1 against #126.
Claude 3.5 Sonnet · Claude Opus 5.5
Claude 3.5 Sonnet or Claude Opus 5.5?
As of Oct 14, 2026, Claude 3.5 Sonnet leads Claude Opus 5.5 in 0 of 4 shared categories.
Claude 3.5 Sonnet or Claude Opus 5.5 for General LLM?
As of Oct 14, 2026, Claude Opus 5.5 leads Claude 3.5 Sonnet in General LLM at #2 against #140.
Claude 3.5 Sonnet or Claude Opus 5.5 for Reasoning?
As of Oct 14, 2026, Claude Opus 5.5 leads Claude 3.5 Sonnet in Reasoning at #1 against #136.
Claude 3.5 Sonnet or Claude Opus 5.5 for Science?
As of Oct 14, 2026, Claude Opus 5.5 leads Claude 3.5 Sonnet in Science at #31 against #119.