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url: https://epoch.ai/data-insights/open-closed-eci-gap date_fetched: 2026-07-05 backfilled: true
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We calculate the average amount of time it takes for the best open-weight models to catch up with state-of-the-art performance according to our internal capability metric, the Epoch Capability Index (ECI). ECI is a composite measure that captures performance across many benchmarks.
Benchmark results featuring the performance of leading AI models on challenging tasks.