# FrontierCode 1.1 Extended

> Cognition's 150-task Extended subset of the FrontierCode 1.1 software-engineering benchmark.

Canonical page: https://benchlm.ai/benchmarks/frontiercode11extended

- Category: [Coding](/coding)
- Last updated: September 27, 2026

## About FrontierCode 1.1 Extended

- Year: 2026
- Tasks: 150 private software-engineering tasks
- Format: Repository task completion with maintainer rubrics
- Difficulty: Frontier coding-agent quality
- Paper: [GPT-5.6 models are now available in Devin](https://devin.ai/blog/gpt-5-6)

BenchLM stores Cognition's published GPT-5.6 scores on FrontierCode 1.1 Extended as display-only evidence. The tasks are private and the results combine a model with the Devin harness, so they are excluded from weighted rankings.

FrontierCode 1.1 Extended is currently displayed on BenchLM for reference, but it is excluded from the weighted scoring formula.

## Leaderboard (7 models)

| Rank | Model | Creator | Score |
|------|-------|---------|-------|
| 1 | [GPT-6 Astra](/models/gpt-6-astra) | OpenAI | 64.5% |
| 2 | [Claude Opus 5.5](/models/claude-opus-5-5) | Anthropic | 63.6% |
| 3 | [Claude Opus 5](/models/claude-opus-5) | Anthropic | 63.6% |
| 4 | [Grok 4.6](/models/grok-4-6) | xAI | 61.3% |
| 5 | [GPT-5.6 Sol](/models/gpt-5-6-sol) | OpenAI | 60.6% |
| 6 | [GPT-5.6 Terra](/models/gpt-5-6-terra) | OpenAI | 55.8% |
| 7 | [GPT-5.6 Luna](/models/gpt-5-6-luna) | OpenAI | 55.1% |

## FAQ

### What does FrontierCode 1.1 Extended measure?

Cognition's 150-task Extended subset of the FrontierCode 1.1 software-engineering benchmark.

### Which model scores highest on FrontierCode 1.1 Extended?

GPT-6 Astra by OpenAI currently leads with a score of 64.5% on FrontierCode 1.1 Extended.

### How many models are evaluated on FrontierCode 1.1 Extended?

7 AI models have been evaluated on FrontierCode 1.1 Extended on BenchLM.

### Does FrontierCode 1.1 Extended affect BenchLM's overall score?

Not directly. FrontierCode 1.1 Extended is still displayed on BenchLM for reference, but it is excluded from the weighted scoring formula.

## Compare Top Models on FrontierCode 1.1 Extended

- [GPT-6 Astra vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-gpt-6-astra)
- [Claude Opus 5.5 vs Claude Opus 5](/compare/claude-opus-5-vs-claude-opus-5-5)
- [Claude Opus 5 vs Grok 4.6](/compare/claude-opus-5-vs-grok-4-6)
- [Grok 4.6 vs GPT-5.6 Sol](/compare/gpt-5-6-sol-vs-grok-4-6)