GPT-5 Chat vs GPT-5 Codex: side-by-side summary

GPT-5 Chat and GPT-5 Codex are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

GPT-5 Chat, from OpenAI, has a 128,000-token context window and is priced by the provider serving it on OpenRouter.

GPT-5 Codex, from OpenAI, has a 400,000-token context window and is priced by the provider serving it on OpenRouter.

Context window

• GPT-5 Chat: 128,000 tokens
• GPT-5 Codex: 400,000 tokens

Price

• GPT-5 Chat: Pricing varies by provider
• GPT-5 Codex: Pricing varies by provider

Provided by

• GPT-5 Chat: OpenAI
• GPT-5 Codex: OpenAI

• GPT-5 Chat model details, providers and pricing
• GPT-5 Codex model details, providers and pricing