Claude Opus 5.5 vs DeepSeek V3.1
As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V3.1 in 3 of 3 shared categories: General LLM, Reasoning, and Long context.
Claude Opus 5.5
Yes. SOTA in Reasoning (tied), Coding (tied), Coding › Agentic (tied), Coding › Web dev, Long context (tied), and Factuality (tied).
DeepSeek V3.1
It used to be. Was SOTA in General LLM.
| Category | Claude Opus 5.5 | DeepSeek V3.1 |
|---|---|---|
| General LLM | #2 · Near-SOTA · General LLM Margin 1.0638297872340416 LMArena leaderboard dataset · Oct 13, 2026 | #124 · #124 in General LLM Margin 65.95744680851064 LMArena leaderboard dataset · Oct 13, 2026 |
| Reasoning | #1 · Co-SOTA · Reasoning Margin 0 LMArena leaderboard dataset · Oct 13, 2026 | #133 · #133 in Reasoning Margin 71.27659574468085 LMArena leaderboard dataset · Oct 13, 2026 |
| Math | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 2026 | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 2026 |
| Science | #31 · #31 in Science Margin — Epoch AI benchmarking hub · Sep 22, 2026 | — |
| Coding | #1 · Co-SOTA · Coding Margin 0 Terminal-Bench Harbor Hub · Oct 6, 2026 | #— · Not enough data Margin — LMArena leaderboard dataset · Oct 13, 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 | #1 · Co-SOTA · Long context Margin 0 LMArena leaderboard dataset · Oct 13, 2026 | #131 · #131 in Long context Margin 69.68085106382979 LMArena leaderboard dataset · Oct 13, 2026 |
| Vision | #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 Opus 5.5: $8.000000000000002 per 1M blended tokens.
DeepSeek V3.1: price per 1M tokens is unset in the catalog.
Claude Opus 5.5: closed weights.
DeepSeek V3.1: open weights.
General LLM: As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V3.1 in General LLM at #2 against #124.
Reasoning: As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V3.1 in Reasoning at #1 against #133.
Long context: As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V3.1 in Long context at #1 against #131.
Claude Opus 5.5 · DeepSeek V3.1
Claude Opus 5.5 or DeepSeek V3.1?
As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V3.1 in 3 of 3 shared categories: General LLM, Reasoning, and Long context.
Claude Opus 5.5 or DeepSeek V3.1 for General LLM?
As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V3.1 in General LLM at #2 against #124.
Claude Opus 5.5 or DeepSeek V3.1 for Reasoning?
As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V3.1 in Reasoning at #1 against #133.
Claude Opus 5.5 or DeepSeek V3.1 for Long context?
As of Oct 15, 2026, Claude Opus 5.5 leads DeepSeek V3.1 in Long context at #1 against #131.