GPT-5.6 Sol
Language modelPrevious generationCard summarizedGPT-5.6 flagship model for complex professional work
Active (legacy)● Re-checked 12 Oct 2026 · 88 facts · 0 corrections · 1 unconfirmedSource: GPT-5.6 System Card (82 pp)
Use it via API
Where to call it
- OpenAI API
gpt-5.6-sol
Supports
- Image input
- Streaming
- Structured outputs
- Reasoning control
- Tool calling
- Web search
- Prompt caching
- Batch API
Good for
- New flagship model; the most capable model OpenAI had deployed
- Largest HealthBench Professional gain since GPT-5 (60.5, +8.7 vs GPT-5.5)
- Slightly fewer factual errors than GPT-5.5; repeats user-flagged errors much less
Watch out for
Overview
GPT-5.6 Sol
GPT-5.6 flagship model for complex professional work
- Cost
- $4.00 in
- Context
- 1.05M
- Input / output
- $4.00 / $20.00
- Max output
- 128K
- Knows up to
- February 2026
- Released
- 9 Jul 2026
The flagship of the GPT-5.6 family. OpenAI treats it as High capability in cybersecurity (below Critical) and in biology and chemistry, and below High in AI self-improvement, and pairs it with its most comprehensive safeguard stack to date, including new activation classifiers. It is better at finding and fixing vulnerabilities than exploiting them, but goes beyond user intent in agentic coding more often than GPT-5.5, though absolute rates stay low. p.2–3, p.34–35, p.71
gpt-5.6-sol- Input / output per 1M
- $4.00 / $20.00
- Context window
- 1.05M
- Max output
- 128K
- Knows up to
- February 2026
- Reasoning
- Configurable (effort none → max)
- Weights
- Closed
About this card. A model card is the maker's own account of a model: what it's for, how it was trained and tested, and where it falls short. This page condenses OpenAI's GPT-5.6 System Card. Every claim carries its source page.