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Tutorial2025-01-128 min read

Claude Code vs Codex: Which AI Coding Assistant is Better?

We tested both AI assistants on real coding tasks. Here's our detailed comparison of strengths, weaknesses, and when to use each one.

K

Kevin M.

Founder


The Contenders

Claude Code by Anthropic and Codex by OpenAI are the two heavyweight CLI-based AI coding assistants. Both can read your codebase, suggest changes, and execute commands. But they have very different personalities.

Test Methodology

We ran both assistants through a series of real-world tasks:

  • Bug fixing in a complex React codebase

  • Writing unit tests for an existing module

  • Refactoring a legacy Express API

  • Implementing a new feature from scratch

  • Code review and optimization suggestions
  • All tests were run on the same codebase, with identical prompts, multiple times to account for variability.

    Results Summary

    TaskClaude CodeCodexWinner

    Bug Fixing9/107/10Claude
    Test Writing8/108/10Tie
    Refactoring9/106/10Claude
    New Features8/108/10Tie
    Code Review9/107/10Claude

    Detailed Analysis

    Bug Fixing

    Claude Code consistently found root causes faster. It asked clarifying questions, traced through call stacks, and proposed fixes that addressed the underlying issue rather than just the symptom.

    Codex was faster but sometimes proposed band-aid solutions. It was excellent at syntax errors but struggled with logic bugs.

    Winner: Claude Code

    Test Writing

    Both performed well here. Claude wrote more comprehensive test cases with better edge coverage. Codex was faster and its tests were more idiomatic for the testing framework we were using (Jest).

    Winner: Tie (depends on your priorities)

    Refactoring

    This is where Claude really shines. It understood architectural patterns, proposed meaningful abstractions, and maintained backwards compatibility without being asked.

    Codex made changes that worked but often lost context about why the code was structured a certain way.

    Winner: Claude Code

    New Features

    Both assistants implemented features correctly. Claude was more verbose in its explanations. Codex was more concise and got to working code faster.

    Winner: Tie

    Code Review

    Claude provided thoughtful, nuanced feedback. It caught security issues, suggested performance improvements, and explained the reasoning behind each suggestion.

    Codex focused more on style and syntax, missing some deeper issues.

    Winner: Claude Code

    When to Use Each

    Use Claude Code when:


  • Working on complex, interconnected systems

  • You need thorough explanations

  • Security and code quality matter

  • Doing large-scale refactoring
  • Use Codex when:


  • You need quick, simple changes

  • Working on boilerplate code

  • Speed is more important than depth

  • You're already in the OpenAI ecosystem
  • Our Recommendation

    For most professional development work, Claude Code is the better choice. Its reasoning capabilities and context understanding are simply superior for complex tasks.

    However, having access to both is ideal. That's why Craaft supports multi-provider — switch between Claude and Codex based on the task at hand.

    Try Both with Craaft

    Craaft lets you use Claude Code and Codex from the same interface. Switch providers with a click, compare results, and use the best tool for each job.

    Start your free trial →

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