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OpenAI API

GPT-5.3-Codex on OpenAI API

Codex · OpenAI

Serverless

Why use GPT-5.3-Codex on OpenAI API?

OpenAI API offers GPT-5.3-Codex with pay-as-you-go pricing at $1.75/1M input tokens. OpenAI is a leading AI research and deployment company dedicated to developing safe and beneficial artificial general intelligence (AGI) for humanity.

Compare GPT-5.3-Codex across 2 providers to find the best fit for your use case

Compare GPT-5.3-Codex Across Providers

ProviderInput (per 1M)Output (per 1M)
OpenRouter$1.75$14.00
OpenAI API$1.75$14.00

Pricing

TypePrice (per 1M)
Input tokens$1.75
Output tokens$14.00

Capabilities

VisionMultimodalReasoningFunction CallingTool UseStructured OutputsCode Execution

About GPT-5.3-Codex

Most capable agentic coding model from OpenAI. Optimized for long-horizon, agentic coding tasks in the Codex CLI and API. Note: GPT-5.3-Codex-Spark is a distinct ChatGPT Pro research preview (not API-accessible).

FAQ

What does GPT-5.3-Codex cost on OpenAI API?

On OpenAI API, GPT-5.3-Codex costs $1.75 per 1M input tokens and $14.00 per 1M output tokens.

What is the context window for GPT-5.3-Codex on OpenAI API?

GPT-5.3-Codex supports a 400,000 token context window on OpenAI API.

How does OpenAI API compare to other GPT-5.3-Codex providers?

GPT-5.3-Codex is available from 2 providers. The cheapest input pricing is $1.75/1M tokens from OpenRouter.

What API model ID do I use for GPT-5.3-Codex on OpenAI API?

Use the model ID gpt-5.3-codex when calling OpenAI API's API.

Who created GPT-5.3-Codex?

GPT-5.3-Codex was created by OpenAI as part of the Codex model family.

Is GPT-5.3-Codex open source?

GPT-5.3-Codex is not open source; the seed data lists it as proprietary.

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Model Specs

Released2026-02-05
Context400K
ArchitectureDecoder Only
Knowledge cutoff2025-08