improvementApril 23, 2026gpt-5.5
GPT-5.5 rolled out to Codex with 400K context, higher coding performance than GPT-5.4, better token efficiency for most users, and an optional Fast mode.
Changelog
Codex changelog
This page shows the recent feature releases, price changes, improvements, and bug fixes recorded for the tool.
improvementApril 16, 2026
Codex expanded beyond pure coding with computer use, in-app browsing, more plugins, memory, automations, image generation, and stronger PR-review workflows.
price-changeApril 2, 2026
Codex pricing began shifting from message-based estimates to token-based credit metering for Plus, Pro, Business, and new Enterprise workspaces.
featureFebruary 2, 2026
OpenAI launched the Codex app and later expanded availability to Windows, making multi-agent desktop workflows a first-class surface.
improvementSeptember 15, 2025gpt-5-codex
OpenAI upgraded Codex with GPT-5-Codex, improved collaboration across terminal, IDE, and web, and added API-key access for developers.
featureMay 16, 2025codex-1
OpenAI introduced Codex as a cloud software engineering agent that could work on parallel tasks in isolated environments.