GPT-5.3-Codex Now Available in GitHub Copilot

GitHub has rolled out GPT-5.3-Codex, OpenAI's latest agentic coding model, to all GitHub Copilot users. Early testing shows the model reaches new high scores on coding, agentic, and real-world capability benchmarks, with up to 25% faster performance than GPT-5.2-Codex on agentic coding tasks.

Where to Access

The model is available to Copilot Pro, Pro+, Business, and Enterprise users through:

• Visual Studio Code (chat, ask, edit, and agent modes)
• github.com
• GitHub Mobile (iOS and Android)
• GitHub CLI
• GitHub Copilot Coding Agent

Users can select GPT-5.3-Codex from the model picker in their preferred environment. Rollout is gradual, so some users may see the option available shortly.

Administrator Configuration

Copilot Enterprise and Copilot Business plan administrators need to enable the GPT-5.3-Codex policy in Copilot settings to grant access to their teams.

What's Improved

The new model features enhanced reasoning and execution capabilities specifically designed for complex, tool-driven, long-running workflows. This makes it particularly well-suited for agentic tasks that require multi-step problem solving and iterative refinement.