OpenAI Codex Models by OpenAI

OpenAIProprietary
OpenAI releases · 44 in the last 12 monthsChangelog →
2 models2025Up to 200k ctx

Last refreshed 2026-09-18. Next refresh: weekly.

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.

Decision facts

Best fit
reasoningcode executioncoding
Capability starting point
Codex Mini Latest with 200k context
Lowest tracked input
Not tracked
Closest related family
GPT-5

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

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
ModelReleasedContextReasoningCode Exec
Codex Mini Latest2025-05200kNoNo

Popular comparisons in this family

Models(2)

Codex Mini Latest

2025-05200k