What it means for leaders

Coding is where model choice pays back fastest, and the lead changes hands within weeks. A new leader is a reason to rerun your own evaluation on your codebase, not to switch vendors on the spot.

What would change the reading: A lead held by a lab outside the top three, or an open-weight model within a few points of the top.

The trend

June 9, 2026September 3, 2026

Every reading

DateValueChangeDetailSource
65.5%+9.2 pointsGPT-6 AstraSource
56.3%+4.3 pointsClaude Fable 5.1Source
52.0%+5.0 pointsClaude Opus 5Source
47.0%—Claude Fable 5Source

Definition and method

What it measures
The highest share of FrontierSWE tasks (long software engineering projects judged on implementation, performance and research) solved by any evaluated model, with the model and lab that hold it.
Population
AI models evaluated on FrontierSWE, as compiled by Epoch AI
Updated
When new models are evaluated
Source
Epoch AI, Benchmarking hub · CC BY 4.0

Caveats

  • Scores come from independent evaluators compiled by Epoch AI, not from the labs, and depend on the settings and tools each run used.
  • The leader is the best result so far, dated by the release of the model that set it; a model evaluated late can take the lead after its release date.
  • Each model is scored with the best agent harness it was run in.

Cite this

Enterprise AI in Numbers, "Top score on FrontierSWE, the benchmark of long software engineering projects", https://lucianoayres.com/ai-brief/data/coding-benchmark-leader/, retrieved October 25, 2026. Data: Epoch AI, Benchmarking hub.

Download every indicator (CSV) · Methodology