AI Rate CardGPT-5.1 Codex · impossibl
GPT-5.1 Codex is a specialised version of OpenAI's GPT-5.1 optimised for software engineering and coding workflows. It is designed for interactive development sessions as well as long, independent runs on complex engineering tasks, and is the base for the smaller GPT-5.1 Codex mini.
Input, $/1M $1.25
Output, $/1M $10.00
Cache read $0.12
Cache write —
Price alerts
API
OpenAI-compatible API: the official OpenAI SDKs work with this base URL. Replace YOUR_API_KEY with your key from the provider.
| API base URL | |
|---|---|
| Endpoint | |
| Model id | |
curl
curl https://api.impossibl.com/v1/chat/completions \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{"model": "openai/gpt-5.1-codex", "messages": [{"role": "user", "content": "Hello!"}], "max_tokens": 256}'Python
import requests
r = requests.post(
"https://api.impossibl.com/v1/chat/completions",
headers={"Authorization": "Bearer YOUR_API_KEY"},
json={
"model": "openai/gpt-5.1-codex",
"messages": [
{
"role": "user",
"content": "Hello!"
}
],
"max_tokens": 256
},
)
print(r.json())JavaScript
const r = await fetch("https://api.impossibl.com/v1/chat/completions", {
method: "POST",
headers: {Authorization: "Bearer YOUR_API_KEY", "Content-Type": "application/json"},
body: JSON.stringify({
"model": "openai/gpt-5.1-codex",
"messages": [
{
"role": "user",
"content": "Hello!"
}
],
"max_tokens": 256
}),
});
console.log(await r.json());Request (JSON)
{
"model": "openai/gpt-5.1-codex",
"messages": [
{
"role": "user",
"content": "Hello!"
}
],
"max_tokens": 256
}Response (JSON)
{
"id": "chatcmpl-...",
"object": "chat.completion",
"model": "openai/gpt-5.1-codex",
"choices": [
{
"index": 0,
"message": {
"role": "assistant",
"content": "Hi! How can I help?"
},
"finish_reason": "stop"
}
],
"usage": {
"prompt_tokens": 9,
"completion_tokens": 12,
"total_tokens": 21
}
}The address is taken from the provider's model list; check it against the provider's documentation.
Source: AI Rate Card, https://airatecard.com/en/c/offer%3Aimpossibl%7Copenai/gpt-5.1-codex, prices checked 2026-11-04; seller's page: https://impossibl.com/models/openai/gpt-5.1-codex
Technical details
ID: offer:impossibl|openai/gpt-5.1-codex