OpenAI
GPT-5.5 Pro
GPT-5.5 Pro is a OpenAI model with 1.05M context, $30 in / $180 out per million tokens, last verified September 3, 2026. Open weights: no. Public-board scores are linked to the publisher; vendor-only figures stay in the watch-out, not on the board.
GPT-5.5 Pro is OpenAI's highest-effort tier for maximal accuracy on the hardest tasks.
Catalog record checked September 3, 2026Individual provider fields may change
| Specification | GPT-5.5 Pro |
|---|---|
| Provider | OpenAI |
| Tier | Frontier |
| Context window | 1.05M |
| Max output | 128K |
| Input / 1M tokens | $30 |
| Output / 1M tokens | $180 |
| Weights | Closed |
| Parameters | Not disclosed |
| Reasoning levels | none, low, medium, high, xhigh, max |
| Modalities | text, image |
| API model id | gpt-5.5-pro |
| Released | April 23, 2026 |
Pricing tiers: Standard $30/$180 per MTok; no cached-input discount. Batch $15/$90.
Verified evidence
Published benchmark results
Each result keeps its source and measurement date visible. A missing benchmark is not treated as a zero.
| Benchmark | Score | Measured | Source |
|---|---|---|---|
| Artificial Analysis Intelligence Index [xhigh] | 60 | 2026-08-14 | Artificial Analysis · View source |
Best for
- Maximum-accuracy reasoning
- Research
- Hard enterprise workloads
Watch out
Source receipts
Catalog figures for this model were checked against the following sources.
- OpenAI — Introducing GPT-5.5 (accessed 2026-08-29)
- OpenAI API pricing (gpt-5.5-pro $30/$180) (accessed 2026-08-29)
Common questions
GPT-5.5 Pro
Answered from the verified figures on this page rather than general guidance.
How much does GPT-5.5 Pro cost per million tokens?
GPT-5.5 Pro is listed at $30 per million input tokens and $180 per million output tokens at standard rates. Output tokens usually dominate real bills, so weigh the output rate more heavily than the input rate. Standard $30/$180 per MTok; no cached-input discount. Batch $15/$90.
What is GPT-5.5 Pro's context window?
GPT-5.5 Pro accepts about 1.05M tokens of context. That only matters if you routinely send very long documents, large codebases, or multi-turn histories that approach that limit.
What is GPT-5.5 Pro best for?
GPT-5.5 Pro is a frontier tier from OpenAI. It suits maximum-accuracy reasoning, research, hard enterprise workloads. At $30/$180 per MTok it is the most expensive OpenAI tier; reserve for work that needs it.