Claude Opus 5 vs Gemini 3.1 Pro
The comparison
On LM Arena, Claude Opus 5 scores higher (1494 Elo vs 1486 Elo), from a smaller review base (19,353 vs 94,728 Arena votes).
As of Aug 12, 2026, Claude Opus 5 is rated 1494 Elo on LM Arena (19,353 Arena votes); Gemini 3.1 Pro is rated 1486 Elo on LM Arena (94,728 Arena votes). No source is blended; each stands on its own.
Claude Opus 5
1494 EloLM Arenahigher
19,353Arena votes
Gemini 3.1 Pro
1486 EloLM Arena
94,728Arena voteslarger base