What is OpenAI Codex used for?

OpenAI Codex is used for code, reasoning, and code execution. The family description and listed model capabilities point to those workloads as the best fit.

How does OpenAI Codex compare to GPT Realtime 2?

OpenAI Codex by OpenAI is strongest where you need code, while GPT Realtime 2 by OpenAI is the closest related family to check for realtime voice. OpenAI Codex has 2 listed variants and reaches up to 200k context, while GPT Realtime 2 reaches up to 131k context, so compare the specs and pricing tables before choosing a production model.

Which OpenAI Codex model should I use?

If price is the main constraint, use the pricing table first because OpenAI Codex does not have complete provider pricing in the local data. For the most capable/latest local choice, evaluate Codex Mini Latest with 200k context.

OpenAI Codex Models by OpenAI

OpenAIProprietary

2 models2025Up to 200k ctx

Details

ResearcherOpenAI

LicenseProprietary

Commercial useCommercial use: conditional

Models2

Released2025

Max context200k

Capabilities

Reasoning1 of 2 models

Code Execution1 of 2 models

Links

Website

About

OpenAI's Codex family of models optimized for software engineering tasks. Built on o3 architecture, trained via reinforcement learning. Powers the OpenAI Codex cloud coding agent with sandboxed execution, GitHub integration, and multi-file reasoning.

Current Variants

Use-when guidance is based on each model's tracked capabilities, context window, release date, and replacement status.

1 in view1 retired

Codex Mini LatestCurrent

Use when the workload needs code and 200k context.

2025-05code200k context

Current OpenAI Codex variants with use-when guidance and lifecycle status
Model	Use when	Released	Signals	Status
Codex Mini Latest	Use when the workload needs code and 200k context.	2025-05	code200k context	Current

Release Timeline

1 release group

2025-05

1 current · 1 retired

Codex 1

code192k contextreasoning

Archived

Codex Mini Latest

code200k context

Current

Specifications(2 models)

OpenAI Codex model specifications comparison
Model	Released	Context	Reasoning	Code Exec
Codex Mini Latest	2025-05	200k	No	No

Popular comparisons in this family

Frequently Asked Questions

What is OpenAI Codex used for?: OpenAI Codex is used for code, reasoning, and code execution. The family description and listed model capabilities point to those workloads as the best fit.
How does OpenAI Codex compare to GPT Realtime 2?: OpenAI Codex by OpenAI is strongest where you need code, while GPT Realtime 2 by OpenAI is the closest related family to check for realtime voice. OpenAI Codex has 2 listed variants and reaches up to 200k context, while GPT Realtime 2 reaches up to 131k context, so compare the specs and pricing tables before choosing a production model.
Which OpenAI Codex model should I use?: If price is the main constraint, use the pricing table first because OpenAI Codex does not have complete provider pricing in the local data. For the most capable/latest local choice, evaluate Codex Mini Latest with 200k context.

Models(2)