GPT-5.5
GPT-5.5 supports demanding coding and professional tasks through text and image input. It remains an available release with a dated April 2026 snapshot.
Its default reasoning differs from GPT-5.4
GPT-5.5 defaults to medium reasoning and supports none through xhigh. It has a 1,050,000-token window. Requests above 272,000 input tokens use higher full-session rates, and eligible regional processing adds a separate premium.GPT-5.5 official model documentation
Keep reasoning settings explicit in comparisons
Practical guidance. When comparing this release with a model that defaults to no reasoning, set the intended effort instead of relying on defaults. Review whether additional reasoning improves the final deliverable. Include latency and the cost of revisions in the comparison.
Specifications & access
| Detail | Value and conditions |
|---|---|
| Access | API |
| Model identifiers | gpt-5.5gpt-5.5-2026-04-23 |
| Context window | 1,050,000 tokens Published model context; input and output share this budget GPT-5.5 official model documentation |
| Maximum output | 128,000 tokens Published maximum output; bounded by the remaining context GPT-5.5 official model documentation |
| Input price | 5 USD per million tokens Standard text processing; inputs up to 272,000 tokens GPT-5.5 official model documentation |
| Output price | 30 USD per million tokens Standard text processing; inputs up to 272,000 tokens GPT-5.5 official model documentation |
| Input and output | text, image in; text outGPT-5.5 official model documentation |
| API routes | Chat Completions (v1/chat/completions); Responses (v1/responses); Batch (v1/batch)GPT-5.5 official model documentation |
Related models
- GPT-5.5 Pro
OpenAI ยท GPT-5.5
GPT-5.5 Pro spends more computation on difficult reasoning tasks.
Launch date not confirmedAPI