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Claude Mythos 5.1 vs Claude Sonnet 5

4 SHARED BENCHMARKS

Across 4 shared benchmarks, Claude Mythos 5.1 scores higher on 4 and Claude Sonnet 5 on 0. The widest gap is Terminal-Bench 4.0, where Claude Mythos 5.1 scores 60.9 against 12.4.

ANTHROPICVSANTHROPIC4 SHARED4–0 HEAD-TO-HEAD

BenchmarkClaude Mythos 5.1MARGINClaude Sonnet 5

BioMysteryBench (Human Difficult)44.139.4

BioMysteryBench (Human Solvable)90.384.9

ProteinGym Hard49.336.6

Terminal-Bench 4.060.912.4

Best tracked score per model per benchmark (default configuration; source-attributed). ↓ marks lower-is-better metrics. Open either model for its full surface, provenance and pricing.

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