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. Your use is subject to OpenAI's Terms & Privacy Policies.
import { streamText } from 'ai'
const result = streamText({ model: 'openai/gpt-5.3-codex-fast', prompt: 'Why is the sky blue?'})Copy link to headingPlayground
Try out GPT 5.3 Codex (Fast) by OpenAI. Usage is billed to your team at API rates. Free users (those who haven't made a payment) get $5 of credits every 30 days.
GPT 5.3 Codex (Fast)
GPT 5.3 Codex (Fast)
Copy link to headingProviders
Route requests across multiple providers. Copy a provider slug to set your preference. Visit the docs for more info. Using a provider means you agree to their terms, listed under Legal.
Copy link to headingThroughput24 hours
P50 throughput on live AI Gateway traffic, in tokens per second (TPS). Visit the docs for more info.
Copy link to headingLatency24 hours
P50 time to first token (TTFT) on live AI Gateway traffic, in milliseconds. View the docs for more info.
Copy link to headingUptime24 hours
Direct request success rate on AI Gateway and per-provider. Uptime reflects the base model. Visit the docs for more info.
Copy link to headingMore models by OpenAI
| Model |
|---|
| 1.1M | 1.6s | 245tps | $1/M$0.20/M Fast $0.40/M+1 more | $6/M$1.20/M Fast $2.40/M+1 more | Read: $0.1/M$0.02/M+1 more Write: $1.25/M$0.25/M+1 more | $10/K + input costs | +4 |   | 07/09/2026 | ||||
| 1.1M | 1.9s | 120tps | $5/M$2.50/M Fast $5/M+1 more | $30/M$15/M Fast $30/M+1 more | Read: $0.5/M$0.25/M+1 more Write: $6.25/M$3.13/M+1 more | $10/K + input costs | +4 | | 07/09/2026 | ||||
| 1.1M | 1.1s | 168tps | $2.50/M$2/M Fast $4/M+1 more | $15/M$12/M Fast $24/M+1 more | Read: $0.25/M$0.2/M+1 more Write: $3.13/M$2.5/M+1 more | $10/K + input costs | +4 | | 07/09/2026 | ||||
| 1.1M | 0.8s | 87tps | $2.50/MFast $5/M+1 more | $15/MFast $30/M+1 more | Read: $0.25/M+1 more Write: — | $10/K + input costs | +4 | | 03/05/2026 | ||||
| 400K | 5.1s | 184tps | $0.05/M | $0.40/M | Read:$0.01/M Write:— | $14/K + input costs | +3 | | 08/07/2025 | ||||
| 131K | 0.1s | 378tps | $0.35/M | $0.75/M | Read:$0.25/M Write:— | — |   +5 | 08/05/2025 |