What changed
GPT-6.1 Sol replaces GPT-6 Sol as OpenAI's efficiency-tier frontier model; on DeepSWE v1.1 it matches GPT-6 Astra at roughly one-fifth of Astra's per-task cost, and beats GPT-5.6 Sol's best score by 6.4 percentage points on the same benchmark.
TL;DR
GPT-6.1 Sol scores within ~2 points of GPT-6 Astra on DeepSWE v1.1, OSWorld 2.0, and AutomationBench at $2/$10 per MTok (cached input $0.10/MTok) — one-fifth of Astra's per-task cost on coding evals.
Developer signal
The benchmark story is unusually strong for an efficiency-tier model. On the four benchmarks OpenAI published — DeepSWE v1.1 (real GitHub issue resolution), AutomationBench (multi-step business workflows), OSWorld 2.0 (computer use), and Terminal-Bench Science 0.1 — GPT-6.1 Sol "nearly matches Astra" across all four. Specifically: OSWorld 2.0, it comes within 2.1 points of Astra at roughly a seventh of the cost per task; AutomationBench, it scores 2.2 points above Claude Opus 5.5 at about a third of the cost. If you're currently using GPT-6 Astra or GPT-6 Sol for coding-agent workloads, this is worth an immediate benchmark run. Pricing: $2/$10 per MTok standard, $0.10/MTok cached input. Currently available in ChatGPT Work and Codex (Plus, Pro, Business, Enterprise, Edu); API availability for general accounts was not confirmed as of this digest — check platform.openai.com.
| Benchmark | GPT-6.1 Sol | GPT-6 Astra | GPT-5.6 Sol | Claude Opus 5.5 |
|---|---|---|---|---|
| DeepSWE v1.1 | matches Astra | — | −6.4 pts vs Sol 6.1 | — |
| AutomationBench | — | — | — | Sol 6.1 +2.2 pts |
| OSWorld 2.0 | within 2.1 pts of Astra | — | — | — |