GPT-5.2 Codex

Closed weights OpenAI December 2025

No estimate

No hardware requirements for this model

The weights for this model have not been published, so it cannot be downloaded or run on your own hardware at any size. It is reachable only through its provider, and no graphics card changes that.

On record

Full specification

Everything on record for this model. Most of it describes how it was trained rather than how it runs — useful context for judging how much work went into it, and how it compares with models built at a different scale.

Origin

Who built this model, where, and when it was published.

Organisation
OpenAI
Organisation type
Industry
Country
United States of America
Published
18 December 2025

What it does

The problem areas the model was built for. A model can carry several of each.

Domain
Language
Task
Language modeling/generation

Size

How large the model is and how much data it was trained on. Parameters are the figure that decides whether it fits on a given graphics card.

Training data
tokens

Availability

Whether you can obtain the model and run it on your own hardware, which is what decides if any of the graphics-card figures on this page apply.

Weights
Closed — provider access only
Model access
API access
Training code
Unreleased

How it is classified

Labels the source dataset applies when tracking notable models, and how confident it is in the entry.

Likely above 10²³ FLOP
Yes
Why it is tracked
Significant use
Record confidence
Likely

Sources

Where this record came from and when it was last checked.

Reference
Introducing GPT-5.2 Codex
Last updated
24 April 2026

What the numbers mean

About this model

GPT-5.2 Codex was published by OpenAI, in United States of America, in December 2025. It comes out of industry.

It works in Language, and is recorded as doing language modeling/generation.

Its weights were never published, so it can only be reached through its provider. No graphics card changes that.

Training and provenance

Its inclusion criterion is significant use.

Answers

GPT-5.2 Codex — common questions

01

When was GPT-5.2 Codex released?

GPT-5.2 Codex was published in December 2025.

02

What is GPT-5.2 Codex used for?

GPT-5.2 Codex works in Language, and is recorded as handling language modeling/generation. These are the areas it was designed around; they describe intent rather than a hard boundary.

03

What GPU do I need to run GPT-5.2 Codex?

None. GPT-5.2 Codex is a closed model — its weights were never published, so it cannot be downloaded or run on your own hardware at any price. It is reachable only through its provider.

04

Is GPT-5.2 Codex open source?

No. GPT-5.2 Codex has not had its weights published, so it exists only as a service controlled by its owner.

05

How many parameters does GPT-5.2 Codex have?

No parameter count has been published for GPT-5.2 Codex, which is why no memory or speed figure appears on this page.

06

Who created GPT-5.2 Codex?

GPT-5.2 Codex was published by OpenAI, based in United States of America, categorised as industry.

Source

Original publication

Record last updated 24 April 2026

The other direction

Looking at it from the other side?

This page starts from the model. If you already own a card and want to know everything it will run, start from the hardware instead.