GPT-5.6 Sol
The flagship tier of the GPT-5.6 family, aimed at complex reasoning, long-horizon agentic work, coding, biology and cybersecurity. In OpenAI's naming the number is the generation and Sol is a durable capability tier, so Sol advances on its own cadence rather than being replaced by the next decimal. Standard short-context pricing is $5/$30 per MTok with cached input at $0.50; requests above 272K tokens are billed at the long-context rate of $10/$45.
GPT-5.6 Sol is a frontier AI model from OpenAI. It costs $5.000 per million input tokens and $30.000 per million output tokens (blended $12.500/M), with a 1,050,000-token context window.
- Frontier reasoning
- Long-horizon agentic execution
- Coding and code review
- Programmatic tool calling in the Responses API
- 1M-token context
- Explicit cache breakpoints with a 30-minute minimum cache life
- Hardest agentic coding tasks
- Multi-step autonomous workflows
- Deep research and analysis
- Security and scientific reasoning
Benchmarks
Also reported by the provider
Results on benchmarks outside the set we compare across models. They are listed for completeness and are deliberately excluded from the bars above and from every ranking on this site, because a score is only comparable against the same benchmark variant. Why benchmark scores do not compare →
- SWE-bench Pro64.6%self-reported by OpenAI · 2026-07 · SWE-bench Verified was not published for GPT-5.6.
- Terminal-Bench 2.188.8%self-reported by OpenAI · 2026-07
- FrontierMath Tier 1–3 (v2)89%self-reported by OpenAI · 2026-07
- FrontierMath Tier 4 (v2)83%self-reported by OpenAI · 2026-07
- MMMU Pro (no tools)83%self-reported by OpenAI · 2026-07
- BrowseComp90.4%self-reported by OpenAI · 2026-07
- OSWorld 2.062.6%self-reported by OpenAI · 2026-07
- Agents' Last Exam52.7%self-reported by OpenAI · 2026-07
- ARC-AGI-37.78%self-reported by OpenAI · 2026-07
More from OpenAI
See all 28 →Frequently asked questions
How much does GPT-5.6 Sol cost?
GPT-5.6 Sol costs $5.000 per million input tokens and $30.000 per million output tokens, for a blended reference rate of $12.500 per million tokens.
What is GPT-5.6 Sol's context window?
GPT-5.6 Sol supports up to 1,050,000 tokens of context in a single request.
What is GPT-5.6 Sol best for?
GPT-5.6 Sol is well suited to Frontier reasoning, Long-horizon agentic execution and Coding and code review.
Who makes GPT-5.6 Sol?
GPT-5.6 Sol is developed and served by OpenAI. It was released in Jul 2026.