OpenAI model

GPT-5.1 Codex

GPT-5.1 Codex is a OpenAI model listed in the NextModel catalog for image understanding, multimodal chat workloads. Its listed price is $1.25 / 1M tokens input and $10 / 1M tokens output, with a 400k token context window.

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

What is GPT-5.1 Codex in NextModel?

GPT-5.1 Codex is a OpenAI model listed in the NextModel catalog for image understanding, multimodal chat workloads. Its listed price is $1.25 / 1M tokens input and $10 / 1M tokens output, with a 400k token context window.

GPT-5.1 Codex via NextModel: 400k-token context; $1.25 / 1M tokens in / $10 / 1M tokens out per 1M tokens. Capabilities: streaming, tool, json.

Best use cases

  • image understanding
  • multimodal chat

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-5.1-codex","messages":[{"role":"user","content":"Reply with OK."}]}'

Switching models only changes the model field.

Try it in the playground

Similar alternatives

OpenAICatalogHealthytypical

GPT-5.1

GPT-5.1 via NextModel: 400k-token context; $1.25 / 1M tokens in / $10 / 1M tokens out per 1M tokens. Capabilities: streaming, tool, json.

$1.25 / 1M tokensInput$10 / 1M tokensOutput400kContext
Best forimage understanding, multimodal chat
StreamingTool callingJSON modeVision
Platform curatedCurated and maintained in the NextModel catalog
View details
OpenAICatalogHealthyfast

GPT-5.1 Codex Mini

GPT-5.1 Codex Mini via NextModel: 400k-token context; $0.25 / 1M tokens in / $2 / 1M tokens out per 1M tokens. Capabilities: streaming, tool, json.

$0.25 / 1M tokensInput$2 / 1M tokensOutput400kContext
Best forimage understanding, multimodal chat
StreamingTool callingJSON modeVision
Platform curatedCurated and maintained in the NextModel catalog
View details
OpenAICatalogHealthytypical

GPT-4.1

GPT-4.1 via NextModel: 1M-token context; $2 / 1M tokens in / $8 / 1M tokens out per 1M tokens. Capabilities: streaming, tool, json.

$2 / 1M tokensInput$8 / 1M tokensOutput1MContext
Best forimage understanding, multimodal chat
StreamingTool callingJSON modeVision
Platform curatedCurated and maintained in the NextModel catalog
View details

Compare GPT-5.1 Codex

GPT-5.1 Codex vs GPT-5.1GPT-5.1 Codex vs GPT-5.1 Codex MiniGPT-5.1 Codex vs GPT-4.1GPT-5.1 Codex vs GPT-4.1 MiniGPT-5.1 Codex vs GPT-4.1 Nano

Reading

Articles that explain GPT-5.1 Codex

FAQ

GPT-5.1 Codex API questions

Start in India

Ready to start building?

Passwordless signup, pay-as-you-go billing, and one OpenAI-compatible endpoint for every model. Create your key and send your first request in minutes.

Get your API keyRead the high-volume quickstart