AI coding tools compared: Cursor vs Codex vs Claude Code

The AI coding tool space has moved fast. A year ago there were a handful of options. Now there are dozens. But three tools have pulled ahead for serious development work: Cursor, OpenAI Codex, and Claude Code. They are all capable. They are not all the same. Here is an honest comparison.

The quick verdict

Cursor is for developers who want the best IDE experience. You work inside the editor, the AI is built in, and the whole thing feels like a single tool rather than a chatbot bolted onto your workflow.

Claude Code is for developers who live in the terminal and work with large codebases. Its 1 million token context window is a genuine competitive advantage on complex projects.

OpenAI Codex is for developers already in the OpenAI ecosystem, and particularly for Python development given the Astral acquisition.

If you are not a developer, all three of these are probably not for you. Bolt, Lovable, or Google AI Studio are better options.

Cursor

Cursor is a fork of VS Code with AI built into the core. If you already use VS Code, switching to Cursor is nearly frictionless. Your extensions, your keybindings, your layout all carry over.

The headline feature is Composer: a multi-file editing mode where you describe a goal and Cursor plans and executes changes across multiple files. Cursor recently shipped Composer 2, its own in-house model that outperforms Claude Opus on coding benchmarks. That is a significant claim, and it holds up in practice. Cursor is fast, context-aware, and genuinely useful for feature development.

Where it wins: IDE experience. If you want AI that fits into your existing workflow without disrupting it, Cursor is the best option. The keyboard shortcuts, the inline suggestions, the visual context of being inside the editor all make it feel natural.

Where it falls short: It is primarily a single-machine, single-project tool. It does not have the same agent autonomy as Claude Code for running commands and iterating on its own.

Pricing: Free tier available. Pro at $20/month.

Claude Code

Claude Code is Anthropic's terminal-based coding agent. It does not try to be an IDE. You run it in your terminal, point it at your project, and give it goals. It reads files, writes files, runs commands, checks results, and iterates. It is more autonomous than Cursor.

The standout feature is the context window. Claude Code benefits from Claude's 1 million token context window, which is roughly 750,000 words. For large codebases, this is a meaningful advantage. Claude Code can read the entire project in a single pass, understand how everything fits together, and make changes that are coherent across the whole codebase rather than just the file in front of it.

This matters most on bigger projects. On a small project, the context window advantage is not noticeable. On a large, complex codebase, it can be the difference between a tool that genuinely understands your project and one that keeps losing the thread.

Where it wins: Large codebases. Terminal-native workflows. Projects where you want the AI to take on a task and work through it autonomously rather than suggesting changes for you to accept one by one.

Where it falls short: It requires comfort with the terminal. If you are used to working in a visual editor, the terminal-first interface is an adjustment.

Pricing: Claude Pro at £18/month required for full access. API usage-based billing available.

OpenAI Codex

Codex is OpenAI's dedicated coding model, accessible through ChatGPT Plus and the API. Two million developers use it every week. It is capable across a wide range of languages and tasks, and it benefits from OpenAI's scale and the depth of its training data.

The strategic context matters here. OpenAI acquired Astral, the team behind uv and Ruff, two Python tools used by 179 million developers monthly. This signals that Codex is becoming the centre of OpenAI's developer strategy, not just another model. For Python development specifically, expect Codex to have a deepening advantage as the Astral tools are integrated.

Codex is also the natural choice if you are already using the OpenAI API in your products. It knows the API, understands the SDK, and can write integrations against it quickly.

Where it wins: Python development. OpenAI ecosystem integration. Accessibility, given that it sits inside ChatGPT and requires no extra tooling to get started.

Where it falls short: It does not have the same IDE integration as Cursor or the same terminal autonomy as Claude Code. It works well as a coding assistant accessed through a chat interface; it is less well suited to running autonomously through a complex multi-file task.

Pricing: ChatGPT Plus at £20/month, or API usage-based.

Head to head

| | Cursor | Claude Code | Codex | |---|---|---|---| | Best for | IDE-integrated development | Large codebases, terminal workflows | Python, OpenAI ecosystem | | Interface | VS Code fork | Terminal | ChatGPT / API | | Context window | Large | 1 million tokens | Large | | Autonomy | Medium | High | Medium | | Price | Free / $20/mo | £18/mo Claude Pro | £20/mo ChatGPT Plus |

What about non-developers?

None of these tools are designed for non-technical business owners. They all assume you can read, understand, and review code. If that is not you, the tools you want are Bolt, Lovable, or Google AI Studio with Antigravity. These are built for building things without writing code. The coding tools above are built for people who write code and want AI to help them do it faster.

The line is blurring over time. As coding tools get more capable and more autonomous, they become accessible to a wider range of people. But right now, if you cannot comfortably review a JavaScript function or understand a Python error message, start with the no-code tools and work your way up.