GPT-5.6 Sol Pro is the same underlying model as GPT-5.6 SolOpens in new tab, served with reasoning.mode set to pro for higher-quality responses on complex tasks.
Cost note: pro mode spends far more reasoning tokens per request, so a typical request costs several times more than the same request on GPT-5.6 Sol and takes much longer to complete. It is intended for hard, high-stakes problems where the extra accuracy justifies the cost. For everyday coding, agentic, and chat workloads, use GPT-5.6 SolOpens in new tab instead.
Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-modeOpens in new tab
Different companies host the same model. OpenRouter routes your request to one of them based on the routing mode you pick — Balanced (price + speed), Nitro (fastest), Floor (cheapest), or Exacto (highest tool-calling accuracy).
The average price customers actually pay for this model, next to the prices providers post. Caching and discounts mean the price actually paid is often well below the listed one.
Throughput is how fast the model writes (tokens per second — higher is better). Latency is total round-trip time (lower is better). TTFT is time-to-first-token — how long before you see anything appear (lower is better).
Uptime is the percentage of the past 3 days that at least one provider was responding to requests. Availability is the percentage of time that inference was successfully served. OpenRouter continuously monitors and uses the next-best provider when one returns an error.
Public apps that send the most traffic to this model. Good signal for what real production workloads look like — and a hint at which use cases this model is best suited for.
Token volume and request traffic to this model over time.
Drop-in code to call this model. OpenRouter's API is OpenAI-compatible — most SDKs work by just swapping the base URL. The only thing that changes between models is the model slug below.
Guides, cookbooks, and tools for building with OpenAI: GPT-5.6 Sol Pro on OpenRouter.
50% off | $4.00$2.00 | $20.00$10.00 | $0.40$0.20 | 7.12s | 77 tps | |
|---|---|---|---|---|---|---|
| $4.00 | $20.00 | $0.40 | 9.39s | 62 tps | ||
Not used in Standard routing:Why these endpoints are not used | ||||||
Flex50% off | $2.00$1.00 | $10.00$5.00 | $0.20$0.10 | 36.56s | 171 tps | |
Fast50% off | $8.00$4.00 | $40.00$20.00 | $0.80$0.40 | 1.68s | 18 tps | |
| $4.40 | $22.00 | $0.44 | 3.44s | 42 tps | ||
P50, best across providers
P50, best provider
When an error occurs in an upstream provider, we can recover by routing to another healthy provider, if your request filters allow it. You can access per-provider uptime data programmatically through the Endpoints API. Learn more about our load balancing and customization options.
GPT-5.6 Sol Pro is the same underlying model as GPT-5.6 Sol, served with reasoning.mode set to pro for higher-quality responses on complex tasks. Cost note: pro mode spends far more reasoning tokens per request, so a typical request costs several times more than the same request on GPT-5.6 Sol and takes much longer to complete.
The GPT-5.6 Sol Pro documentation on OpenRouter includes the GPT-5.6 Migration Guide cookbook. The quickstart covers API keys and your first request, and the API reference lists every parameter.
GPT-5.6 Sol Pro costs $2.00/M input tokens and $10.00/M output tokens, with separate rates for Cache Read at $0.20/M tokens, Cache Write at $2.50/M tokens, and Web Search at $10.00/1K calls.
GPT-5.6 Sol Pro has a 1,050,000 token context window. It supports up to 128,000 completion tokens.
Yes. GPT-5.6 Sol Pro accepts tools and tool_choice for function calling. It also supports structured outputs via a JSON schema in response_format.
Yes. OpenAI caches prompts of 1024 tokens or more automatically, and GPT-5.6 Sol Pro bills a cache write on each cached prompt whether or not the cached prefix is read again. To turn caching off for a request, set prompt_cache_options.mode to "explicit" at the request root and do not mark any content block with prompt_cache_breakpoint. Explicit mode disables OpenAI-managed breakpoints, so a request with none of your own has no cacheable prefix and is billed at the plain input rate. See the prompt caching guide.
GPT-5.6 Sol Pro accepts files such as PDFs, images, and text as input and returns text.
GPT-5.6 Sol Pro is served by 2 providers on OpenRouter: OpenAI and Azure. Requests are routed to the best available provider, with automatic failover to the others, and you can pin or exclude providers with provider routing.
GPT-5.6 Sol Pro was released on July 9, 2026. Its knowledge cutoff is February 16, 2026.