GPT-5.5 Pro
OpenAI · released Apr 24, 2026
- Type
- Closed
- Input
- $30.00
- Output
- $180.00
- Cached
- None held
List price · per 1M tokens · OpenAI at 1.1M context · source ↗
Our take
Written Sep 4, 2026GPT-5.5 Pro is OpenAI's flagship reasoning system that accepts text, images and files in a single request of up to around one million tokens. It is built for complex document and image analysis, but carries a steep premium and no measured quality scores in our data.
Use this when you need to analyse entire codebases, books or long conversation histories in one pass, or when your workflow mixes images, uploaded files and text in a reasoning-heavy pipeline. Pick it if OpenAI's ecosystem integration matters more than raw speed or the ability to run elsewhere. Skip it if cost per output token is a constraint, if you need fast throughput, or if you want measured benchmark scores to justify the spend.
The case for it
- One-million-token request limit enables single-pass analysis of documents hundreds of pages long.
- Tiered speed options from the same provider let you trade throughput for cost.
The case against it
- Output rates are six to twelve times the input rate on every tracked offer, with modest throughput for the price point.
- No benchmark scores, chat Elo, reasoning, coding or safety scores are unverified in our data.
- Proprietary weights with no published parameter count and no open alternative.
How good is it?
We hold no score for this model.
So there is no figure here for everyday use, coding, agent work or writing. That is a gap in our data, not a low score.
Where to rent it
Prices checked 4 hours ago — each listing carries its own date.
OpenAI, through OpenRouter
The lab is the cheapest at this context. The strip above and this offer are the same one, compared at 1.1M of context. One cheaper row below is outside that comparison: a non-standard pricing tier.
- per 1M tokens
- $30.00 in / $180.00 out
- Context served
- 1.1M
- Throughput
- ~5 tok/s
| Provider | In / out per 1M tokens | Context | Throughput | Trains on prompts | Logs prompts | Zero retention |
|---|---|---|---|---|---|---|
| OpenAIflex tierThrough OpenRouter | $15.00 / $90.00checked 4 hours ago | 1.1M128K max reply | 2 tok/s | No | Yesunknown period | Unknown |
| OpenRouterOpenRouter's own listing | $30.00 / $180.00checked 4 hours ago | 1.1M | not measured | Unknown | Unknown | Unknown |
| OpenAIThrough OpenRouter | $30.00 / $180.00checked 4 hours ago | 1.1M128K max reply | 5 tok/s | No | Yesunknown period | Unknown |
OpenRouterAcross the 3 listings we hold: 2 say they do not train on prompts, 0 say they do and 1 does not say. 0 appear in the zero-retention registry we check; the rest are unknown to us.
What each host's API supports
From the parameter list each endpoint publishes. Streaming is omitted: nothing we hold reports it, for any model.
| Provider | Tool calling | JSON output | Strict schema |
|---|---|---|---|
| OpenAIflexThrough OpenRouter | ✓ | ✓ | ✓ |
| OpenRouterOpenRouter's own listing | ✓ | ✓ | ✓ |
| OpenAIThrough OpenRouter | ✓ | ✓ | ✓ |
Tool calling: 3 of 3 listings say yes. JSON output: 3 of 3 listings say yes. Strict schema: 3 of 3 listings say yes.
Models people weigh against GPT-5.5 Pro
When we formed this view
Recent changes
What moved
first indexed by our pipelineEach date is the day we first saw the change, or the day the maker announced it.
What we do not know about this model yet
- No independent board has scored it, so we hold no quality figures at all.
- Nothing we hold says whether an endpoint streams, so we do not show it either way.
- 1 of 3 listings does not say whether it trains on prompts.
- We hold no cached-input rate for any of its listings.
- We hold no batch or off-peak rate for any of its listings.
Licence and identifiers
What the licence allowsWe hold no licence record for this model. Inside are the identifiers you need to pull it — its Hugging Face repo where we have one, our slug and a machine-readable card.
Licence
We hold no licence record for this model, and no record of published weights either — so we can neither summarise its terms nor point you at the weights.
Identifiers
- Takes in, gives back
- Text, images and documents in, text out
- Catalogue slug
- openai-gpt-5-5-pro