Who ranks #1 on the FrontierCode 1.1 Extended leaderboard?
As of September 1, 2026, Claude Fable 5.1 by Anthropic ranks #1 on FrontierCode 1.1 Extended at 63.6%. API pricing is $10.00/M input and $50.00/M output.
As of September 1, 2026, Claude Fable 5.1 is #1 for FrontierCode 1.1 Extended at 63.6%. Ranked by the FrontierCode 1.1 Extended score 2 models in this index have a published FrontierCode 1.1 Extended score. FrontierCode 1.1 Extended leaderboard with live API prices. FrontierCode 1.1 Extended — Cognition's longer agentic PR-fix suite.
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As of September 1, 2026, Claude Fable 5.1 by Anthropic is #1 for FrontierCode 1.1 Extended at 63.6%. Ranked by the FrontierCode 1.1 Extended score This board also tracks FrontierCode 1.1 Extended. Next on the same board: Claude Mythos 5.1. This frontiercode 1.1 extended leaderboard ranks models by FrontierCode 1.1 Extended. Scores come from public evals. Prices are the live API rates in the table above.
Sources: OpenAI API pricing (https://developers.openai.com/api/docs/pricing); Anthropic Claude API pricing (https://platform.claude.com/docs/en/about-claude/pricing); Gemini API pricing (https://ai.google.dev/gemini-api/docs/pricing)
| Rank | Model | FrontierCode 1.1 Extended | Input /M | Output /M |
|---|---|---|---|---|
| 1 | Claude Fable 5.1 | 63.6% | $10.00 | $50.00 |
| 2 | Claude Mythos 5.1 | 63.6% | $10.00 | $50.00 |
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As of September 1, 2026, Claude Fable 5.1 by Anthropic ranks #1 on FrontierCode 1.1 Extended at 63.6%. API pricing is $10.00/M input and $50.00/M output.
The current FrontierCode 1.1 Extended ranking as of September 1, 2026 is 1. Claude Fable 5.1 at 63.6%; 2. Claude Mythos 5.1 at 63.6%.
Claude Fable 5.1 currently leads FrontierCode 1.1 Extended and is also the cheapest scored model on this page, at $10.00/M input and $50.00/M output ($60.00 blended).
Not automatically. Claude Fable 5.1 leads FrontierCode 1.1 Extended, but a cheaper scored model can be the better production choice if the quality gap is small. Use the table to weigh FrontierCode 1.1 Extended against input/output price, context window, and related evals.
Scores and API prices on this page are refreshed from published evals and provider rates. The snapshot is labeled September 1, 2026. Treat it as a current index, not a one-off blog post.
FrontierCode 1.1 Extended — Cognition's longer agentic PR-fix suite. This page ranks models that have published a FrontierCode 1.1 Extended score, with live API token prices on the same row.
This page is the FrontierCode 1.1 Extended leaderboard. Models are sorted by FrontierCode 1.1 Extended, with input and output token prices on the same row so you can weigh score against cost. Official boards often omit price; that comparison is the point of this index.
Official eval pages own the methodology. This page keeps the published FrontierCode 1.1 Extended score next to live API $/M so you can pick a production SKU, not only a trophy number.