GPT-5.5 vs Claude Opus 4.7: 2026 Flagship Showdown

GPT-5.5Claude Opus 4.7
arenaElo14321420
humanEval94.293.1
sweBench6664.3
mmlu9392.3
gpqa68.765.2
aime9288
Price in/out ($/M)$12 / $48$15 / $75

Our verdict

GPT-5.5 edges Opus 4.7 on Arena Elo and HumanEval by a hair, while Opus 4.7 still holds the 1M context crown and long-horizon agent stability. For voice + multimodal, GPT-5.5. For coding agents and long-doc legal work, Opus 4.7.

GPT-5.5 · Claude Opus 4.7 · All AI model comparisons