# Claude Opus 5.5 vs Kimi K3.1 Pro

As of Nov 3, 2026, Claude Opus 5.5 leads Kimi K3.1 Pro in 4 of 4 shared categories: General LLM, Science, Coding › Web dev, and Legal.

## Pricing

Claude Opus 5.5: $8 per 1M blended tokens.

Kimi K3.1 Pro: $4 per 1M blended tokens.

Claude Opus 5.5: closed weights.

Kimi K3.1 Pro: closed weights.

## Benchmarks side by side

| Benchmark | Claude Opus 5.5 | Kimi K3.1 Pro |
| --- | ---: | ---: |
| Excel Modeling Benchmark (EMB) | 75.8 | 70.0 |
| Finance Agent | 67.8 | 61.5 |
| Legal Research Bench | 50.5 | 37.5 |
| LMArena WebDev | 1810 | 1695 |
| MysteryMechanism | 49.5 | 26.1 |
| ProofBench | 100 | 91.0 |
| Tax Agent Bench | 45.6 | 24.9 |
| Vals Index | 70.2 | 62.5 |
| Vibe Code Bench | 90.3 | 84.9 |

## Verdict

As of Nov 3, 2026, Claude Opus 5.5 leads Kimi K3.1 Pro in 4 of 4 shared categories: General LLM, Science, Coding › Web dev, and Legal.

- Which to pick, General LLM: As of Nov 3, 2026, Claude Opus 5.5 leads Kimi K3.1 Pro in General LLM at #1 against #51.
- Which to pick, Science: As of Nov 3, 2026, Claude Opus 5.5 leads Kimi K3.1 Pro in Science at #2 against #15.
- Which to pick, Coding › Web dev: As of Nov 3, 2026, Claude Opus 5.5 leads Kimi K3.1 Pro in Coding › Web dev at #1 against #8.
- Which to pick, Legal: As of Nov 3, 2026, Claude Opus 5.5 leads Kimi K3.1 Pro in Legal at #5 against #22.

As of Nov 3, 2026, Claude Opus 5.5 is tied for state of the art in General LLM (since Oct 20, 2026; sources LMArena Text (style-controlled, overall) and Vals Index; methodology v1.0).

As of Nov 3, 2026, Kimi K3.1 Pro is ranked #8 in Coding › Web dev (since Nov 3, 2026; sources LMArena WebDev; methodology v1.0).

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