Question 1

What is GPT-5.6 Sol?

Accepted Answer

GPT-5.6 Sol is a model from OpenAI, released on Jul 9, 2026. GPT-5.6 Sol is the flagship model in OpenAI's GPT-5.6 series. It is suited for complex reasoning, coding, and agentic workflows, and is particularly strong at command-line and multi-step coding tasks and long-horizon problem solving.

Question 2

How much does GPT-5.6 Sol cost?

Accepted Answer

On the Respan gateway, input starts at $2.00 per 1M tokens on OpenRouter, and output starts at $10.00 per 1M tokens on OpenRouter, after gateway discounts. Averaged across 6 providers, it costs $4.00 per 1M input tokens and $21.67 per 1M output tokens.

Question 3

Which providers serve GPT-5.6 Sol on Respan?

Accepted Answer

6 providers serve GPT-5.6 Sol: OpenRouter, Azure OpenAI, OpenAI, Perplexity, Inference.net, and Tera. Azure OpenAI, Perplexity, and Tera require your own provider API key (BYOK).

Question 4

What is GPT-5.6 Sol's context window?

Accepted Answer

GPT-5.6 Sol accepts up to 1.1M tokens of context on its largest provider route.

Question 5

How do I use GPT-5.6 Sol with the Respan gateway?

Accepted Answer

Point any OpenAI-compatible SDK at https://api.respan.ai/api/ with your Respan API key and set the model to "openai/gpt-5.6-sol". To set it up with a coding agent, copy the agent setup prompt at the top of this page.

Question 6

How fast is GPT-5.6 Sol?

Accepted Answer

Over the last 30 days of requests through the Respan gateway, the fastest provider was Azure OpenAI at 361 tokens per second, and the lowest response latency was 1.3 seconds on OpenRouter. Speed varies with request size and provider.

Question 7

Where does GPT-5.6 Sol rank on the Respan Index?

Accepted Answer

GPT-5.6 Sol scores 60.6 out of 100 on the Respan Index v1.1, ranking #10 of 138 models. By category: Coding 45.2, Agents 68.0, Reasoning 67.4, Knowledge & language 69.6, and Human preference 56.5. The Respan Index combines independent and lab-reported benchmark results into one score, using benchmark data collected by llmmetric.com.

Question 8

How does GPT-5.6 Sol score on benchmarks?

Accepted Answer

GPT-5.6 Sol has 38 published benchmark scores, including WeirdML 89.4%, BALROG 60%, and GPQA Diamond 94.6%. Each score links to where it was published; the data is collected by llmmetric.com.

Provider	Context	Input	Output
OpenRouter`openrouter/openai/gpt-5.6-sol`	1.1M	$2.00/M	$10.00/M
Azure OpenAIBYOK only`azure/gpt-5.6-sol`	1.1M	$4.00/M	$20.00/M
OpenAI`openai/gpt-5.6-sol`	1.1M	$4.00/M	$20.00/M
PerplexityBYOK only`perplexity/openai/gpt-5.6-sol`	1.1M	$4.00/M	$20.00/M
Inference.net`inference_net/gpt-5.6-sol`	1.1M	$5.00/M	$30.00/M
TeraBYOK only`tera/openai/gpt-5.6-sol`	1.1M	$5.00/M	$30.00/M

GPT-5.6 Sol

Providers

Certified where it counts.

Pricing

Cost by volume

Throughput and latency

Output speed

Time to first token

Response latency

Benchmarks

Respan Indexv1.1

Coding10

Apps

GPT-5.6 Sol FAQ

Works with your entire stack

Built for AI agents.
Break less.
Ship more.

Agents5

Reasoning8

Math6

Knowledge4

Multimodal1

Arena3

Other1