OpenAI

GPT-5.3-Codex

GPT-5.3-Codex by OpenAI through the RelaySwitch API: $1.75 per million input tokens, $14.00 per million output tokens. Pay by card or crypto (Card, Apple Pay, PayPal, USDT, USDC, BTC, ETH, SOL). No KYC.

Input / M$1.75OpenAI list: $1.75
Cached input / M$0.175OpenAI list: $0.175
Output / M$14.00OpenAI list: $14.00

Specs

Model id
gpt-5.3-codex
Developer
OpenAI
Context window
400K tokens
Max output
128K tokens
Input
text, image
Released
2026-02-24

Call it

bash
1curl https://api.relayswitch.io/v1/chat/completions \
2 -H "Authorization: Bearer $RELAYSWITCH_KEY" \
3 -H "Content-Type: application/json" \
4 -d '{
5 "model": "gpt-5.3-codex",
6 "messages": [{"role": "user", "content": "Hello"}]
7 }'

Any OpenAI SDK works: set the base URL to https://api.relayswitch.io/v1 and the model to gpt-5.3-codex. Get a key or read the docs.

More from OpenAI

FAQs

GPT-5.3-Codex: questions

Payment, keys and billing in short.

Open the console

A key in under a minute

Get a key

Or email hello@relayswitch.io

Run GPT-5.3-Codex today

Top up by card or crypto and send "gpt-5.3-codex".

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