GPT-6.1 Sol is OpenAI’s GPT-6.1 model for complex coding, computer use and professional work, which OpenAI describes as near-Astra performance at a lower cost. GPT-6.1 Sol reads a 1,050,000-token context, returns up to 128,000 tokens and takes text and images. On reAPI, GPT-6.1 Sol is billed per token at OpenAI’s standard rate.
Start with the prompt in the composer or choose an example.
Credit-based — 1 credit = $0.001 USD. Pay only for completed generations.
One 1K-token prompt with a 1K-token answer at the cheapest tier.
| Category | Standard · prompts up to 272K input tokens | Long context · prompts over 272K input tokens |
|---|---|---|
| Input | $2.0 Price · 1M tokens | $4.0 Price · 1M tokens |
| Output | $10.0 Price · 1M tokens | $15.0 Price · 1M tokens |
| Cache read | $0.1 Price · 1M tokens | $0.2 Price · 1M tokens |
| Cache write | $2.5 Price · 1M tokens | $5.0 Price · 1M tokens |
GPT-6.1 Sol is a model in OpenAI’s GPT-6.1 line, released on September 29, 2026, as the newer version of GPT-6 Sol. OpenAI describes GPT-6.1 Sol as near-Astra performance for complex work at a lower cost, and points it at complex coding, computer use and professional work. GPT-6.1 Sol accepts text and images and returns text, with the same 1,050,000-token context window as GPT-6 Astra. Its model ID is gpt-6.1-sol. On reAPI, GPT-6.1 Sol is served through the OpenAI-compatible Chat Completions endpoint and billed per token.
Real-world workflows and production use cases you can build and ship with this model.
Paste a function, a diff or a failing test and ask GPT-6.1 Sol for the bug, the fix and the test that proves it. For larger changes, have GPT-6.1 Sol plan a migration step by step and flag the risky parts before anyone touches the code.
Read the API docs
Contracts, specs and policy manuals fit in one GPT-6.1 Sol request. Ask for every obligation and deadline as a table, or pin the answer to a JSON schema so the result drops straight into your system.
Give GPT-6.1 Sol a messy brief, a data export or a set of competing requirements and ask for a ranked plan with the trade-offs spelled out. Raise reasoning to high or xhigh when GPT-6.1 Sol has to weigh many constraints at once.
OpenAI lists GPT-6.1 Sol at one fifth of GPT-6 Astra’s input and output rate, and its cached input at 5% of the input rate. reAPI bills GPT-6.1 Sol at OpenAI’s standard rate from the same balance as every other model. The pricing table on this page shows the live GPT-6.1 Sol numbers.
OpenAI’s GPT-6 Sol page points to GPT-6.1 Sol as the newer Sol model. GPT-6.1 Sol keeps GPT-6 Sol’s input and output price, halves its cached-input rate and moves the knowledge cutoff to April 30, 2026.
In our tests on reAPI, a 40-token max_completion_tokens cap stopped generation at exactly 40 tokens, and n: 2 returned two choices. The cap counts reasoning tokens too, so the visible answer can be shorter or even empty; you pay for what is generated.
GPT-6.1 Sol and GPT-6 Astra share the same context window, output limit and knowledge cutoff. OpenAI positions GPT-6 Astra as its most capable model and GPT-6.1 Sol as near-Astra performance at a lower cost.
Source: OpenAI model documentation, reviewed October 28, 2026. Official specifications do not establish a measured quality difference. On reAPI, GPT-6.1 Sol currently accepts reasoning levels low to xhigh.
Sign in to reAPI and create a key under API keys. The same key reaches GPT-6.1 Sol and every other model on the platform, billed from one balance.
OpenSet the base URL to https://reapi.ai/api/v1 and use the key you just created. Any client that already speaks OpenAI Chat Completions can call GPT-6.1 Sol without an SDK change.
OpenSet the model field to gpt-6.1-sol and post your messages. GPT-6.1 Sol starts at medium reasoning by default; raise it to high or xhigh for the hardest tasks.
Opencurl https://reapi.ai/api/v1/chat/completions \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "gpt-6.1-sol",
"messages": [
{ "role": "user", "content": "Hello" }
],
"reasoning_effort": "medium",
"max_completion_tokens": 16000,
"stream": true
}'Rejected synchronously with the failing field named. Check enum values, ranges, and URL fields — nothing is charged.
401 means a missing or invalid Bearer key; 402 means the reserve exceeds your balance. Manage keys and credits in the console.
Reference material and outputs pass automated moderation. Rejected tasks fail with a clear error and a full refund.
A task that reaches a failed state is never charged — the reserve refunds automatically. Keep the task id and retry when ready.
Common questions about this model.
Pricing
GPT-6.1 Sol pricing from OpenAI's price page: input, output, cache reads and writes, the 272K tier, Batch, Fast and Ultrafast, plus worked cost examples.
Comparisons
GPT-6.1 Sol vs GPT-6 Astra from OpenAI's docs: positioning, price per token, cache rates, reasoning levels, context and Ultrafast, plus where GPT-6 Sol fits.
Comparisons
GPT-6.1 Terra vs 6.1 Sol from OpenAI's docs: positioning, reasoning levels, context, knowledge cutoff and price, plus a pick-by-task table and where Luna fits.
Try it in the playground or grab an API key to integrate now.
