Model · OpenAI · Text
GPT-5.5
OpenAI's flagship model — a unified general-purpose and reasoning model positioned as a new class of intelligence for coding and professional work. The current successor to the GPT-4o / o-series lines.
- Modality
- Text
- License
- Proprietary (Proprietary)
- Context window
- 1,050,000 tokens
- Released
- April 23, 2026
- Last verified
- June 8, 2026
- Runs locally
- No
- Also handles
- vision
Strengths
- ~1M-token context window (128k max output)
- Unified frontier model — strong general, coding, and reasoning in one
- December 2025 knowledge cutoff
Weaknesses
- Closed weights — API/product only
- Flagship pricing ($5 input / $30 output per MTok)
Try it
| Where | Type | Notes |
|---|---|---|
| OpenAI API | hosted-api | API key required |
| Azure OpenAI | hosted-api | Enterprise / regional |
| ChatGPT | product | Free / paid tiers |
Version history
- GPT-5.5 Apr 2026 Current
- GPT-5.4 mini Mar 2026
- GPT-5.3-Codex Feb 2026
Official sources
- Model docs docs
- Announcement announcement
Change log
- — Initial entry (2026-06-08 catalog refresh, Tier 3). Flagship released 2026-04-23; the successor OpenAI positions above GPT-4o and the o-series.
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