YepAPI

Command Palette

Search for a command to run...

OpenAIText Generation/v1/ai/chat

GPT-5.6 Sol

Access GPT-5.6 Sol through one API key. OpenAI GPT-5.6 Flagship for Coding & Agents.

GPT-5.6 Sol is the flagship of OpenAI's GPT-5.6 series, the generation between GPT-5.5 and GPT-6. Sol 5.6 is a strong choice for coding agents that work in a terminal, large refactors, and long agent runs that need a capable model at a lower rate than GPT-6 Astra.

No credit card required. Takes 30 seconds.

2,400+

Developers

1.2M+

API calls served

100+

Endpoints

$0.01

Per call

Yep, that's it.

Try it live

Send a message and see GPT-5.6 Sol respond in real time.

POST/v1/ai/chat

Maximum tokens in the response.

Real-time tokens

Hit "Send Request" to see the response

Context Window

1.1M tokens

Max Output

128K tokens

Input Price

$2.95 / 1M tokens

Output Price

$14.77 / 1M tokens

Strengths

✓
GPT-5.6 flagship

The top model of the GPT-5.6 series, tuned for complex reasoning, coding and agentic work.

✓
Command-line coding

Particularly strong at shell-driven and multi-step coding tasks, the workload behind most coding agents.

✓
1M token context, 128K output

Handles up to 1,050,000 input tokens and returns up to 128,000 output tokens per call.

✓
Tools and structured output

Function calling, JSON schema outputs, seeds and reasoning effort control.

Quick start

Copy this snippet and start making calls with GPT-5.6 Sol.

const res = await fetch('https://api.yepapi.com/v1/ai/chat', {
  method: 'POST',
  headers: {
    'x-api-key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "model": "openai/gpt-5.6-sol",
    "messages": [
      {
        "role": "user",
        "content": "Explain API gateways in 2 sentences."
      }
    ],
    "maxTokens": 256
  }),
});
const { data } = await res.json();
console.log(data.message.content);

Why use GPT-5.6 Sol through YepAPI?

✓One API key for all models — no separate accounts
✓OpenAI SDK compatible — just change the base URL
✓No monthly minimums — pay per token
✓Switch models with one line of code
✓Full provider passthrough — citations, search results, and all extras included
✓Streaming and non-streaming support on every model
✓Works with Cursor, Claude, LangChain, and any LLM tool
✓Unified billing across all providers

GPT-5.6 Sol API — pricing, context window & access

GPT-5.6 Sol is the flagship of OpenAI's GPT-5.6 series, the generation between GPT-5.5 and GPT-6. It pairs a 1,050,000-token context window with up to 128,000 output tokens per response, at $2.95 per 1M input and $14.77 per 1M output tokens through YepAPI.

Through YepAPI you call GPT-5.6 Sol on an OpenAI-compatible endpoint with a single key — the same key that reaches GPT-6, Claude, Gemini, Grok and the SEO, SERP and scraping APIs. Input: text, images, files.

What is GPT-5.6 Sol?

GPT-5.6 Sol is the flagship of OpenAI's GPT-5.6 series, the generation between GPT-5.5 and GPT-6. It is built for complex reasoning, coding and agentic workflows, and is particularly strong at command-line and multi-step coding tasks, with a 1,050,000-token context window and up to 128,000 output tokens. A GPT-5.6 Sol Pro variant runs it in a higher-effort reasoning mode. It accepts text, images, files as input, handles up to 1,050,000 tokens of context and returns up to 128,000 output tokens per call.

Build with GPT-5.6 Sol via YepAPI

YepAPI serves GPT-5.6 Sol on the OpenAI-compatible /v1/ai/chat endpoint. Point your base URL at YepAPI, add your key, and set the model string to gpt-5.6-sol (or the full openai/gpt-5.6-sol). Function calling, structured outputs and reasoning settings pass straight through, and switching to any other model on the platform is a one-string change per request.

GPT-5.6 Sol API pricing — $2.95 / 1M input, $14.77 / 1M output

GPT-5.6 Sol costs $2.95 per 1M input tokens and $14.77 per 1M output tokens through YepAPI, pay per token with no minimums. Failed calls are never charged, and every request is itemised in your dashboard API Logs so you can see exactly what a 128,000-token response cost.

GPT-5.6 Sol use cases

Sol 5.6 is a strong choice for coding agents that work in a terminal, large refactors, and long agent runs that need a capable model at a lower rate than GPT-6 Astra.

Try GPT-5.6 Sol free

Every new YepAPI account includes $5 in free credit with no card required — enough to test GPT-5.6 Sol on your own prompts before committing to paid usage. Create an account, copy your key, and call gpt-5.6-sol right away.

Start generating in 30 seconds

$5 free credit on signup. No credit card required. Pay per call.

What developers say

“Switched from SerpAPI and cut our SERP costs by 80%. Same data quality, way simpler billing.”

Marcus T.

SEO Platform Founder

“One API key for AI models, SERP data, and web scraping. Saved us from managing 4 separate providers.”

Priya S.

Full-Stack Developer

“The $5 free credit let us prototype our entire rank tracking feature before committing. No other API does that.”

Jake R.

Indie Hacker

Frequently asked questions

GPT-5.6 Sol is the flagship of OpenAI's GPT-5.6 series, the generation between GPT-5.5 and GPT-6. Sol 5.6 is a strong choice for coding agents that work in a terminal, large refactors, and long agent runs that need a capable model at a lower rate than GPT-6 Astra.

Input tokens cost $2.95 per 1M tokens and output tokens cost $14.77 per 1M tokens through YepAPI. No monthly minimums — you only pay for what you use.

Sign up for a free API key, then send requests to the /v1/ai/chat endpoint.

GPT-5.6 Sol supports a 1.1M token context window with up to 128K output tokens per request.

Ready to use GPT-5.6 Sol?

$5 free credit on signup. No credit card required. Pay per call.

Explore more models