GPT-5.6 Sol Pro

OpenAIopenai/gpt-5.6-sol-proProviders: 5
Inputi$4per 1M tokens
Outputi$20per 1M tokens
Contexti1.1M1,050,000 tokens
ReleasedJul 9, 2026Max output: 128K

About this model

GPT-5.6 Sol Pro is an AI model from OpenAI, made available through the API on July 9, 2026. It can read up to 1,050,000 tokens in one request, roughly 1,969 pages of text, and write up to 128,000 tokens in a single answer. Besides text, it accepts files such as PDFs and images as input.

Through the API it costs $4 per million input tokens and $20 per million output tokens. It is among the more expensive models we track, a price usually reserved for the most capable, flagship-class models.

It supports extended reasoning: it can "think" step by step before answering, which helps on maths, code and complex questions. It can call tools and functions, so developers can connect it to search, databases or other software.

Quality scores

Rankings →

Not rated yet. Independent test results usually appear a few weeks after a model is released.

Benchmark data: Epoch AI, licensed CC BY 4.0

Where to use it

Companies that serve this model through an API: 5. Prices per million tokens, cheapest first.

ProviderInputiOutputiContextiUptime (24 h)i
OpenAIOfficialCheapest
$1$51.1M97.5%
OpenAIOfficial
$2$101.1M100.0%
OpenAIOfficial
$4$201.1M100.0%
Azure
$4$201.1M100.0%
Azure
$4.40$221.1M100.0%

Availability and prices come from OpenRouter’s public API and are refreshed daily. Uptime is the share of successful requests over the last 24 hours. Some providers run a compressed version of open models (fp8, int4), which is cheaper but can be slightly less accurate.

Use it in your code

Call GPT-5.6 Sol Pro through OpenRouter’s OpenAI-compatible API: create a key on openrouter.ai, then run one of these examples.

curl https://openrouter.ai/api/v1/chat/completions \
  -H "Authorization: Bearer $OPENROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "openai/gpt-5.6-sol-pro", "messages": [{"role": "user", "content": "Hello! What can you do?"}]}'

The same code works with every model on this site: only the model ID changes. Many labs also offer their own API and SDK.

What it costs in practice

  • 1,000 chat replies
    ≈ 500 tokens in, 300 out each
    $8.00
  • Summarise a 100-page document
    ≈ 50,000 tokens in, 1,000 out
    $0.22
  • An app with 10,000 requests a day for a month
    ≈ 1,000 tokens in, 400 out each
    $3,600

Cost calculator →

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Frequently asked questions

How much does GPT-5.6 Sol Pro cost?
GPT-5.6 Sol Pro costs $4 per million input tokens and $20 per million output tokens through the API. For example, 1,000 chat replies of about 500 tokens in and 300 out cost around $8.00.
What is the context window of GPT-5.6 Sol Pro?
GPT-5.6 Sol Pro can read up to 1,050,000 tokens in one request, about 1,969 pages of text. It can write up to 128,000 tokens in a single answer.
Is GPT-5.6 Sol Pro open source?
No. GPT-5.6 Sol Pro is a closed model: its weights are not published, so you use it through OpenAI’s own apps and API, or through cloud providers.
Who makes GPT-5.6 Sol Pro?
GPT-5.6 Sol Pro is made by OpenAI. It became available through the API on July 9, 2026.
Can GPT-5.6 Sol Pro read images?
Yes. Besides text, it accepts files such as PDFs and images as input.
What are the alternatives to GPT-5.6 Sol Pro?
Models with a similar price from other companies include Qwen3.8 Max Prime, Claude Opus 5.5 and MiMo-V2.6-Pro-UltraSpeed. You can compare them side by side on this page.