GPT-5.3 Codex
OpenAIGPT-5.3 Codex is optimized for agentic coding tasks in Codex or similar environments. OpenAI calls it the most capable agentic coding model to date. It supports low, medium, high, and xhigh reasoning effort settings, and it has a dedicated prompting guide.
The real OpenAI model
Same weights, same API, same answers. We change only how you pay for it: one key for every maker, one bill, no separate account to open. Every figure on this page comes from OpenAI’s own page — check it.
Maker's own pagePrice
input / output · per 1M tokensOpenAI
Official price
More pricing details: speeds
| Speed | OpenAI |
|---|---|
| Priority · faster | $3.50 / $28.00 |
Context
400,000
up to 128,000 out
64,000 by default here
Modalities
Released
Feb 5, 2026
Knows up to Aug 31, 2025
What it would cost you
1000 tokens is roughly 750 English words.
How it is served
Requests are retried automatically if a provider is unavailable.
Similar models
Models built for the same kind of work, at a similar price.
We do not mark up the price of tokens. It is the same price the maker charges.
Use it from your code
from openai import OpenAI
# Works with the official openai package (pip install openai)
client = OpenAI(
base_url="https://api.flintbeam.com/v1",
api_key="sk-live-your-api-key"
)
response = client.chat.completions.create(
model="openai/gpt-5.3-codex",
messages=[
{"role": "system", "content": "You are an experienced software engineer."},
{"role": "user", "content": "Describe the architecture of a distributed cache."}
],
temperature=0.7,
max_tokens=1500
)
print(response.choices[0].message.content)