gpt-5.3-codex
OpenAI/Proprietary/2 providers
GPT-5.3-Codex is OpenAI’s most advanced agentic coding model, combining the frontier software engineering performance of GPT-5.2-Codex with the broader reasoning and professional knowledge capabilities of GPT-5.2.MoreLess
Which id to call
gpt-5.3-codexRequesty routes this id across every provider serving gpt-5.3-codex, picking on price and health and failing over automatically. The id stays valid when a provider changes underneath it.
From /1M input
$1.75
OpenAI Inc.
Context
400K
128K output
Endpoints
2
2 regions
Regions
2
chat
Capabilities 6/8
2 endpoints / 2 regions
Providers serving gpt-5.3-codex
Provider prices, per 1M tokens. Pay as you go adds 5%, or 0% on your own keys.
| Rank | Privacy | ||||||
|---|---|---|---|---|---|---|---|
| 1 | OpenAI Inc. | Global | 400K | $1.75 | $14.00 | $0.17 | no-train |
| 2 |  Microsoft Azure AI | eastus2 | 400K | $1.75 | $14.00 | $0.17 | zdr |
A column is blank where no qualifying sample exists, and every row links to that provider's endpoint page.
model=
Which id to call
One base url, https://router.requesty.ai/v1, and one key for every id here.
gpt-5.3-codexRequesty routes this id across every provider serving gpt-5.3-codex, picking on price and health and failing over automatically. The id stays valid when a provider changes underneath it.
OpenAI compatible
Call it in three lines
Change the base url, use your Requesty key, set the model to any id on the left. Existing OpenAI SDK code needs no other edit.
123456789101112131415from openai import OpenAI client = OpenAI( api_key="YOUR_REQUESTY_API_KEY", base_url="https://router.requesty.ai/v1", ) response = client.chat.completions.create( model="gpt-5.3-codex", messages=[ {"role": "user", "content": "Explain quantum computing in one paragraph."}, ], ) print(response.choices[0].message.content)
Artificial Analysis
Benchmark scores
Graduate-level physics, chemistry & biology questions designed to resist Googling.
Artificial Analysis Intelligence Index: a composite of multiple evaluations measuring overall model capability.
Scores from artificialanalysis.ai. They measure the model, not the provider, so they are the same on every endpoint above.
6
More from OpenAI
Reference
gpt-5.3-codex questions
Which providers serve gpt-5.3-codex?
gpt-5.3-codex is available from 2 providers through Requesty: OpenAI Inc., Microsoft Azure AI. All endpoints share one OpenAI-compatible API and one key, and Requesty fails over between them automatically.
How much does gpt-5.3-codex cost?
Pricing starts at $1.75 per million input tokens and $14.00 per million output tokens on OpenAI Inc., the cheapest endpoint. Prices vary by provider and region; the table above shows every endpoint. Those are the upstream provider rates: pay as you go adds 5% on top, or 0% if you bring your own provider keys.
Is gpt-5.3-codex open weights?
No. gpt-5.3-codex is a proprietary model from OpenAI, served through OpenAI's own API and licensed cloud platforms.
What is the context window of gpt-5.3-codex?
gpt-5.3-codex supports up to 400K tokens of context, with up to 128K output tokens per response. Some providers expose a smaller window; check the per-endpoint context column above.
How do I use gpt-5.3-codex with the OpenAI SDK?
Install the OpenAI SDK, set base_url to "https://router.requesty.ai/v1", set your API key to your Requesty key, and set the model to "gpt-5.3-codex" or any endpoint id from the table above. The quickstart section shows Python, JavaScript and cURL snippets.
Should I call gpt-5.3-codex by its managed id or a provider id?
Use the managed id, "gpt-5.3-codex". Requesty picks which of the 2 providers serves each request based on price and health, and fails over when one degrades, so the id keeps working while the routing changes underneath it. Send a provider id like "openai/gpt-5.3-codex" only when you need one specific deployment and want no failover.
Route gpt-5.3-codex through one endpoint
One key for 2 providers on this model and 600+ others. No markup on provider prices, automatic failover, caching built in.