# GPT-5.5 Pro

GPT-5.5 Pro is an OpenAI language model released Apr 24, 2026; OpenAI's newest language model in our dataset is GPT-6.1 Terra. Proprietary, API access only. OpenAI's GPT-5.5 Pro, released Apr 24, 2026 for harder problems; it uses more compute and has no cached-input discount. Verified against vendor sources on Oct 26, 2026.

Last verified: 2026-10-26 · Evidence: Reported · Canonical: https://theagenticweekly.com/models/gpt-5-5-pro · JSON: https://theagenticweekly.com/api/models/gpt-5-5-pro

## Key facts

| Fact | Value | Source |
|---|---|---|
| Vendor | OpenAI |  |
| Released | Apr 24, 2026 | https://developers.openai.com/api/docs/changelog |
| API id | `gpt-5.5-pro` | https://developers.openai.com/api/docs/models/gpt-5.5-pro |
| Context window | 1,050,000 tokens (1.05M) | https://developers.openai.com/api/docs/models/gpt-5.5-pro |
| Max output | 128,000 tokens | https://developers.openai.com/api/docs/models/gpt-5.5-pro |
| Input | text, image | https://developers.openai.com/api/docs/models/gpt-5.5-pro |
| Output | text | https://developers.openai.com/api/docs/models/gpt-5.5-pro |
| Licence | Proprietary (API) | https://developers.openai.com/api/docs/models/gpt-5.5-pro |
| Pricing | $30 in / $180 out per 1M tokens | https://developers.openai.com/api/docs/models/gpt-5.5-pro |

## What we tested

Nothing yet. We have not run GPT-5.5 Pro ourselves, so every fact here is Reported from the sources below.

## Sources

- [OpenAI API changelog](https://developers.openai.com/api/docs/changelog)
- [OpenAI model page: GPT-5.5 Pro](https://developers.openai.com/api/docs/models/gpt-5.5-pro)

Data licence: CC BY 4.0. Data: Agentic Weekly (https://theagenticweekly.com), CC BY 4.0.