Using GPT-5.3-Codex on OpenRouter

Quick Start

1. 1
   Create an account at OpenRouter and generate an API key.
2. 2
   Use the OpenRouter SDK or REST API to call openai/gpt-5.3-codex — see the documentation for request format.
3. 3
   You'll be billed $1.75/1M input, $14.00/1M output tokens. See full pricing.

Code Examples

About OpenRouter

OpenRouter provides a unified interface for Large Language Models with better pricing, improved uptime, and no subscription requirements. Route across providers for cost optimization and reliability.

OpenRouter is a multi-provider LLM aggregator offering unified API access to 300+ models from all major labs and emerging providers, with automatic failover for reliability.

Pricing on OpenRouter

Capabilities

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).