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GPT 5.3 Codex (Fast)

GPT-5.3-Codex advances both the frontier coding performance of GPT‑5.2-Codex and the reasoning and professional knowledge capabilities of GPT‑5.2, together in one model, which is also 25% faster. This enables it to take on long-running tasks that involve research, tool use, and complex execution.

Input and output price
Input $3.50, Output $28, Per 1M tokens
24h uptime
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Base model
Get API keyRead the docs
import { streamText } from 'ai'


const result = streamText({
  model: 'openai/gpt-5.3-codex-fast',
  prompt: 'Why is the sky blue?'
})
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