GPT-5.6 Sol Pro
OpenAI · released Jul 9, 2026
- Type
- Closed
- Input
- $2.00
- Output
- $10.00
- Cached
- $0.20
List price · per 1M tokens · OpenAI at 1.1M context · source ↗
Our take
Written Sep 4, 2026GPT-5.6 Sol Pro is OpenAI's proprietary flagship reasoning model that accepts text, images and files across a 1.05 million token request limit. It offers a wide speed-for-cost trade-off, from a slow budget tier to a fast Azure-hosted option, though no benchmark scores are available to verify its capabilities.
Choose this for analysing very long documents or codebases in a single pass, or for batch work where low cost beats speed. Use the Azure tier if you need low latency in production. Skip it if you need measured quality data to compare against alternatives, or if 13 tokens per second is too slow for your interactive use case.
The case for it
- 1.05 million token request limit — among the largest we track, supporting full books or large codebases in one pass.
- Wide speed range: the fastest tier is more than ten times quicker than the slowest, with several stops between.
- Azure's fastest tier offers more speed than OpenAI's own at lower cost.
The case against it
- No benchmark scores in our data — no measured Elo, reasoning, or coding scores to verify capability claims.
- The slowest tier is likely too sluggish for real-time chat or streaming use.
- Premium speed demands a steep price jump from the entry tier.
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
- $2.00 in / $10.00 out
- Context served
- 1.1M
- Throughput
- ~86 tok/s
| Provider | In / out per 1M tokens | Context | Throughput | Trains on prompts | Logs prompts | Zero retention |
|---|---|---|---|---|---|---|
| OpenAIflex tierThrough OpenRouter | $1.00 / $5.00checked 4 hours ago | 1.1M128K max reply | 27 tok/s | No | Yesunknown period | Unknown |
| OpenAIThrough OpenRouter | $2.00 / $10.00checked 4 hours ago | 1.1M128K max reply | 86 tok/s | No | Yesunknown period | Unknown |
| OpenRouterOpenRouter's own listing | $4.00 / $20.00checked 4 hours ago | 1.1M | not measured | Unknown | Unknown | Unknown |
| Microsoft Azure AIThrough OpenRouter | $4.00 / $20.00checked 4 hours ago | 1.1M128K max reply | 98 tok/s | No | No | Confirmed |
| OpenAIfast tierThrough OpenRouter | $4.00 / $20.00checked 4 hours ago | 1.1M128K max reply | 18 tok/s | No | Yesunknown period | Unknown |
| Microsoft Azure AIeuThrough OpenRouter | $4.40 / $22.00checked 4 hours ago | 1.1M128K max reply | 29 tok/s | No | No | Confirmed |
OpenRouter
Microsoft Azure AIAcross the 6 listings we hold: 5 say they do not train on prompts, 0 say they do and 1 does not say. 2 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 | ✓ | ✓ | ✓ |
| OpenAIThrough OpenRouter | ✓ | ✓ | ✓ |
| OpenRouterOpenRouter's own listing | ✓ | ✓ | ✓ |
| Microsoft Azure AIThrough OpenRouter | ✓ | ✓ | ✓ |
| OpenAIfastThrough OpenRouter | ✓ | ✓ | ✓ |
| Microsoft Azure AIeuThrough OpenRouter | ✓ | ✓ | ✓ |
Tool calling: 6 of 6 listings say yes. JSON output: 6 of 6 listings say yes. Strict schema: 6 of 6 listings say yes.
Models people weigh against GPT-5.6 Sol Pro
When we formed this view
Recent changes
What moved
GPT-5.6 Sol Pro moved on 2 Azure listings: Azure (EU region): input −20% ($5.50 → $4.40 per 1M tokens), output −33% ($33.00 → $22.00 per 1M tokens), cache read −20% ($0.55 → $0.44 per 1M tokens), cache write −20% ($6.88 → $5.50 per 1M tokens); Azure: input −20% ($5.00 → $4.00 per 1M tokens), output −33% ($30.00 → $20.00 per 1M tokens), cache read −20% ($0.50 → $0.40 per 1M tokens), cache write −20% ($6.25 → $5.00 per 1M tokens)What moved
input −20% ($1.25 → $1.00 per 1M tokens), output −33% ($7.50 → $5.00 per 1M tokens), cache read −20% ($0.125 → $0.100 per 1M tokens), cache write −20% ($1.56 → $1.25 per 1M tokens)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 6 listings does not say whether it trains on prompts.
- 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-5-6-sol-pro