Codex API for OpenAI's coding models — GPT-5.3 Codex, GPT-5.2 Codex, GPT-5.1 Codex Max, GPT-5.1 Codex Mini and more, all through one OpenAI-compatible API.
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gpt-5.1-codex-max
Transparent pricing with no hidden fees. Pay only for what you use.
Per 1M tokens
| Rate | GoldCurrent price | Platinum | Diamond | Official | Your savings |
|---|---|---|---|---|---|
| Input | 10~$1 | 9.5~$0.95 | 9~$0.9 | 12.5~$1.25 | 20% |
| Output | 80~$8 | 76~$7.6 | 72~$7.2 | 100~$10 | 20% |
Call every OpenAI Codex model from one place: GPT-5.3 Codex, GPT-5.2 Codex, the GPT-5.1 Codex family and GPT-5 Codex. Compare Codex pricing and pick the right model for each coding task.
50K+
Active Users
99.9%
Uptime
2x
Faster
70%
Cost Savings
Why developers use the Codex API for coding workloads
What developers build with OpenAI Codex models
Start using OpenAI Codex models in minutes
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Generate an API key to call Codex models programmatically.
Use the playground above or integrate via API with the OpenAI SDK.
Common questions about Codex API pricing, keys and usage
The Codex API gives you access to OpenAI's Codex models, the coding-focused members of the GPT family. On APIMart you can call GPT-5.3 Codex, GPT-5.2 Codex, GPT-5.1 Codex, GPT-5.1 Codex Max, GPT-5.1 Codex Mini and GPT-5 Codex with one API key.
Codex API pricing is based on token usage: input and output tokens are billed separately, and each Codex model has its own rate. Check the pricing table on this page for current per-million-token prices.
GPT-5.1 Codex Mini is the cheapest Codex model on APIMart, with the lowest input and output token rates in the series. For more demanding coding work, try GPT-5.3 Codex or GPT-5.1 Codex Max.
Sign up for APIMart, open the API Keys page in your dashboard and create a new key. The same key calls every Codex model, the GPT API and all other models on the platform, with pay-as-you-go billing and no subscription.
The API is compatible with the OpenAI SDK. Point the base URL to APIMart, authenticate with your APIMart API key and set the model parameter to a Codex model ID such as gpt-5.3-codex.
Codex models are OpenAI GPT models specialized for coding, so they are the natural choice for code generation, review and refactoring. For general chat, writing or reasoning tasks, see the full lineup on our GPT API page. Both use the same API key and billing.
No. APIMart does not offer free credits for the Codex API. All Codex models are pay-as-you-go by token usage, you only pay for successful requests, and Gold members get 20% off all prices.
Yes. Prices shown on this page are Gold member prices, already 20% off. Platinum and Diamond members save even more, up to 28%, and you only pay for successful requests.
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