GPQA Diamond is a graduate-level multiple-choice benchmark in biology, physics, and chemistry. Each question is written by a subject-matter expert and designed so that even domain specialists need careful reasoning to identify the correct answer. We run the same fixed question set across provider endpoints to compare model capability, routing, and the practical cost of solving difficult scientific problems.
Last benchmark run
Fugu Ultra leads GPQA Diamond at 94.6% as of Sep 21, 2026, 4:49 PM UTC. The same fixed GPQA Diamond question set and scoring are held fixed across production provider endpoints. The headline row uses default routing where available; otherwise, it uses a representative provider result.
A snapshot of this leaderboard is published in the benchmark-leaderboard open dataset (filter on the benchmark column), regenerated daily with no API key required. The current snapshot was generated on . It is licensed under CC BY 4.0, so you can reuse and republish it with attribution to OpenRouter.
Column definitions, methodology and redaction rules are in the dataset README.
OpenRouter (2026). GPQA Diamond results on OpenRouter, 2026-09-21 snapshot. https://openrouter.ai/benchmarks/gpqa-diamond. Licensed under CC BY 4.0.