claude code vs cursor vs codex i used all three on the same project for six weeks and here is the honest side by side nobody else gives you
Three AI coding tools. Same project. Six weeks. Claude Code, Cursor, and OpenAI Codex are all described as AI coding agents but they work so differently that comparing them feels like comparing a drill, a screwdriver, and a power tool set. I used all three on a real Unity game project and tracked what each one did better, worse, and in a way I had not expected. This is the honest personal comparison.
Marcus Webb
July 8, 2026
Test setup: Unity 6 game project with 52 scripts. Six weeks total. Two weeks per tool as primary coding tool. Same 15 tasks: 5 bug fixes, 4 new features, 3 refactors, 2 test additions, 1 performance investigation. Costs: Claude Code via Claude Pro $20 per month plus approximately $28 in API costs over two weeks. Cursor Pro $20 per month flat. Codex via ChatGPT Pro $200 per month, two week prorated cost approximately $100. This price difference is the first and most significant data point.
What Each Tool Actually Is
These three tools are often described interchangeably as AI coding assistants but they represent three distinct categories. Cursor is an AI-augmented editor. You write code inside it and the AI assists in real time through completions, chat, and multi-file editing. Claude Code is an agentic CLI tool. You give it a task in your terminal and it reads your codebase, plans the work, writes files, runs tests, and iterates with limited supervision. Codex is an agentic cloud tool. Similar to Claude Code in its autonomous approach but it runs in a cloud sandbox rather than on your machine. Understanding this distinction before comparing them is more useful than any head-to-head benchmark.
Pricing: The Number That Changes Everything
- Cursor Pro: $20 per month flat (€18.40 / £15.80 / ₹1,660). Unlimited completions, 500 fast premium requests, full Composer. Predictable cost.
- Claude Code: Claude Pro at $20 per month gives access to the tool. Heavy autonomous task use generates additional API token charges. In my two-week test period I incurred $28 in API costs on top of the $20 Pro subscription. Light use stays within Pro limits. Heavy agentic task use scales in cost.
- OpenAI Codex: $200 per month via ChatGPT Pro (€184 / £158 / ₹16,620). No additional usage charges within the plan. The flat rate is the entire cost.
- The cost reality: Cursor costs 10x less than Codex per month. Claude Code can be comparable to Cursor on light use or significantly more on heavy agentic use. The comparison between the tools only makes sense if you factor in this price difference from the start.
The 15 Tasks: How Each Tool Performed
- Bug fixes (5 tasks): Cursor resolved 4 of 5 correctly on first attempt. Claude Code resolved all 5, using its ability to run the project and see actual error output rather than relying on code analysis alone. Codex resolved all 5 with the most detailed root cause explanations. Edge to autonomous tools (Claude Code and Codex) on complex bugs.
- New feature implementation (4 tasks): Cursor was fastest on features touching 1-3 files with clear requirements. Claude Code handled the most complex feature (a complete save system across 11 files) with one pass and correct test coverage. Codex handled the same type of task well but the cloud sandbox meant I could not see intermediate steps as clearly.
- Refactoring (3 tasks): Claude Code and Codex both handled large refactors better than Cursor because they can execute changes, run tests, and fix failures in a loop. Cursor Composer is strong but the autonomous verification loop is a genuine advantage for refactoring with test suites.
- Test suite additions (2 tasks): Codex best here. It generated tests, ran them, saw which failed, and fixed the code rather than just the tests. This test-driven loop produced more reliable test coverage than either Cursor or Claude Code delivered in my testing.
- Performance investigation (1 task): Codex best. It profiled, identified the bottleneck, proposed and tested the fix, and reported results. Cursor and Claude Code both suggested fixes but neither autonomously verified the performance improvement.
Where Each Tool Clearly Wins
- Cursor wins on: daily active coding velocity, real-time pair programming feel, inline completions while writing, cost for equivalent output on standard coding tasks. For 80 percent of daily coding work Cursor at $20 per month delivers more value per dollar than either alternative.
- Claude Code wins on: large codebase context at lower cost than Codex, autonomous multi-file task completion, running tests as part of the development loop, and availability on your local machine rather than a cloud sandbox. Best middle option between Cursor and Codex.
- Codex wins on: autonomous test-and-verify loops, performance investigation, complex tasks where seeing an AI plan, execute, and verify end-to-end matters more than cost. The strongest autonomous coding experience but at a price that justifies it only for specific high-value task types.
Mistakes Comparing These Three Tools
- Running identical prompts on all three and comparing output quality: Cursor is optimised for interactive editing with short context. Claude Code and Codex are optimised for autonomous task execution with full codebase context. The same prompt produces different results because the tools have different interaction models. Compare appropriate tasks per tool.
- Not accounting for the total workflow time: Codex tasks can take several minutes to complete. I would submit a task and continue working in Cursor while it ran. The wall clock time comparison between tools misses the fact that Codex tasks run asynchronously.
- Expecting one tool to replace the others entirely: after six weeks I kept all three. Cursor for daily active development, Claude Code for medium complexity autonomous tasks, Codex reserved for the specific task types where its test-verify loop justified the cost.
Who Should Use Each Tool
- Use Cursor if: you want the best AI-assisted daily coding experience at a reasonable cost. The right choice for the majority of developers.
- Use Claude Code if: you regularly need autonomous multi-file task completion and want lower cost than Codex. Strong middle option for developers who have outgrown Cursor Composer for complex tasks.
- Use Codex if: complex autonomous tasks with test verification are a significant part of your daily work and you can justify $200 per month against that specific value.
Final Thoughts
Six weeks across all three tools produced a clear hierarchy based on my specific work. Cursor is the daily driver. Claude Code handles the complex autonomous tasks that Cursor Composer cannot complete in one pass. Codex earns its place for the specific task types where autonomous test-verify loops matter. The $200 per month for Codex is only justified for developers whose primary bottleneck is exactly the type of autonomous task Codex is built for. For everyone else Cursor plus occasional Claude Code is the right combination at a fraction of the cost.