Claude Sonnet 5.5 vs O3
As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in 6 of 6 shared categories: General LLM, Reasoning, Math, Science, Long context, and Factuality.
Claude Sonnet 5.5
Yes. SOTA in co-SOTA in Coding, co-SOTA in Coding › Agentic and co-SOTA in Vision.
O3
It used to be. Was SOTA in General LLM.
| Category | Claude Sonnet 5.5 | O3 |
|---|---|---|
| General LLM | #27 · #27 in General LLM Margin 18.367346938775512 LMArena leaderboard dataset · Oct 13, 2026 | #78 · Was SOTA · General LLM Margin 53.06122448979592 LMArena leaderboard dataset · Oct 13, 2026 |
| Reasoning | #18 · #18 in Reasoning Margin 13.013698630136986 LMArena leaderboard dataset · Oct 13, 2026 | #90 · Was SOTA · Reasoning Margin 62.32876712328767 LMArena leaderboard dataset · Oct 13, 2026 |
| Math | #4 · #4 in Math Margin 6.666666666666671 Epoch AI benchmarking hub · Sep 28, 2026 | #20 · Was SOTA · Math Margin 42.22222222222222 Epoch AI benchmarking hub · Apr 16, 2025 |
| Science | #3 · #3 in Science Margin — Epoch AI benchmarking hub · Sep 28, 2026 | #67 · #67 in Science Margin — Epoch AI benchmarking hub · Apr 16, 2025 |
| Coding | #1 · Co-SOTA · Coding Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 | #— · Not enough data Margin — Epoch AI benchmarking hub · Apr 16, 2025 |
| Coding › Agentic | #1 · Co-SOTA · Coding › Agentic Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 | — |
| Coding › Web dev | #3 · Near-SOTA · Coding › Web dev Margin 1.8691588785046775 LMArena leaderboard dataset · Oct 13, 2026 | — |
| Long context | #11 · #11 in Long context Margin 7.482993197278915 LMArena leaderboard dataset · Oct 13, 2026 | #110 · Was SOTA · Long context Margin 74.82993197278913 LMArena leaderboard dataset · Oct 13, 2026 |
| Vision | #1 · Co-SOTA · Vision Margin 0 Epoch AI benchmarking hub · Sep 28, 2026 | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 9, 2026 |
| Factuality | #16 · #16 in Factuality Margin 12.68656716417911 LMArena leaderboard dataset · Oct 13, 2026 | #105 · #105 in Factuality Margin 79.1044776119403 LMArena leaderboard dataset · Oct 13, 2026 |
| Abstraction (ARC) | — | #37 · #37 in Abstraction (ARC) Margin — Epoch AI benchmarking hub · Apr 16, 2025 |
Claude Sonnet 5.5: $4.000000000000001 per 1M blended tokens.
O3: $3.5 per 1M blended tokens.
Claude Sonnet 5.5: closed weights.
O3: closed weights.
General LLM: As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in General LLM at #27 against #78.
Reasoning: As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in Reasoning at #18 against #90.
Math: As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in Math at #4 against #20.
Science: As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in Science at #3 against #67.
Long context: As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in Long context at #11 against #110.
Factuality: As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in Factuality at #16 against #105.
Claude Sonnet 5.5 or O3?
As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in 6 of 6 shared categories: General LLM, Reasoning, Math, Science, Long context, and Factuality.
Claude Sonnet 5.5 or O3 for General LLM?
As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in General LLM at #27 against #78.
Claude Sonnet 5.5 or O3 for Reasoning?
As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in Reasoning at #18 against #90.
Claude Sonnet 5.5 or O3 for Math?
As of Oct 14, 2026, Claude Sonnet 5.5 leads O3 in Math at #4 against #20.