Gpt 5.1 Codex API
Run openai/gpt-5.1-codex through FastInfra's OpenAI-compatible API.
Pay per token, no subscription, routed to the cheapest available provider.
Gpt 5.1 Codex pricing
Billed per token used. Prices sync automatically from wholesale providers.
| Direction | Price per 1M tokens |
|---|---|
| Input | $1.31 |
| Output | $10.50 |
Served by 1 provider
Requests route to OpenRouter by default (cheapest).
Pin a specific provider with the :provider suffix.
| Provider | Upstream model ID |
|---|---|
| openrouter | openai/gpt-5.1-codex |
Call Gpt 5.1 Codex in 30 seconds
Works with any OpenAI SDK — change the base URL and API key only.
Python
from openai import OpenAI
client = OpenAI(api_key="YOUR_API_KEY", base_url="https://api.fastinfra.ai/v1")
response = client.chat.completions.create(
model="openai/gpt-5.1-codex",
messages=[{"role": "user", "content": "Hello!"}]
)
print(response.choices[0].message.content)curl
curl https://api.fastinfra.ai/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!"}]
}'Gpt 5.1 Codex — common questions
How much does the openai/gpt-5.1-codex API cost?
On FastInfra, openai/gpt-5.1-codex costs $1.3125/1M input, $10.5/1M output tokens. Billing is per token used, with no subscription.
Is openai/gpt-5.1-codex compatible with the OpenAI SDK?
Yes. FastInfra exposes openai/gpt-5.1-codex through an OpenAI-compatible endpoint at https://api.fastinfra.ai/v1 — point any OpenAI SDK at that base URL with a FastInfra API key and keep your existing code.
Which providers serve openai/gpt-5.1-codex?
openai/gpt-5.1-codex is available from 1 provider(s): openrouter. Requests route to OpenRouter by default (cheapest); append ":provider" to the model ID to pin one.
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