OpenAI model

GPT 5 Codex API

The public model id is openai/gpt-5-codex. It has an input price of $1.25 per 1M tokens. Walk away if you need a published context window or a published CacheSafety score, because both are missing.

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OpenAIPlatform curatedCatalog
ThinkingFunction Calling
Input price$1.25 / 1M tokens
Output price$10 / 1M tokens
Context length400k tokens
Max output8.2k tokens

What is GPT 5 Codex API in NextModel?

The public model id is openai/gpt-5-codex. It has an input price of $1.25 per 1M tokens. Walk away if you need a published context window or a published CacheSafety score, because both are missing.

GPT-5 Codex via NextModel: 400k-token context; $1.25 / 1M tokens in / $10 / 1M tokens out per 1M tokens. Capabilities: streaming.

Best use cases

  • Call it when you want the GPT-5 Codex catalog entry and accept that context and first-party CacheSafety are unpublished.
  • It is a price match with its OpenAI siblings, so use this id when the exact Codex name matters.
  • You need the listed capabilities on this catalog entry.

When not to use

  • Do not call it if you need a published context window or a first-party CacheSafety score.
  • Both are unpublished in this catalog snapshot.
  • Also skip it if you require a release date or independent quality score, because those are not in the notes.

OpenAI-compatible code example

request.sh
curl https://api.nextmodel.app/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $NEXTMODEL_API_KEY" \
  -d '{"model":"openai/gpt-5-codex","messages":[{"role":"user","content":"Reply with OK."}]}'

Switching models only changes the model field.

Try it in the playground

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Compare GPT-5 Codex

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Reading

Articles that explain GPT-5 Codex

FAQ

GPT-5 Codex API questions

What model id do I send for GPT 5 Codex?

Send openai/gpt-5-codex to https://api.nextmodel.app/v1 with your OpenAI SDK. If that id is missing from /v1/models, the page is stale.

What does the catalog list for price and context?

GPT 5 Codex is listed at $1.25 / 1M tokens input and $10 / 1M tokens output. Context window: not published in catalog.

What should I treat as unverified?

Do not call it if you need a published context window or a first-party CacheSafety score. Both are unpublished in this catalog snapshot.

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