"Is Cursor AI safe?" is a fair question to ask before you point an AI editor at your codebase. The honest answer is nuanced: Cursor is safe enough for most everyday and commercial coding when you turn on Privacy Mode and avoid feeding it secrets — but it is not a local-only tool, so your code does travel to third-party model providers, and that matters more the more sensitive your code is. Below is what actually happens to your data, what Cursor documents, and how to use it more safely.
How Cursor handles your code
Cursor is an AI-first code editor (a fork of VS Code) built around large language models. To generate completions, chat answers, edits and agentic actions, it sends relevant parts of your code and context to model providers such as Anthropic and OpenAI, gets a response, and applies it in your editor. That round trip is the core of how it works — and the core of the privacy question.
A few mechanisms are worth understanding:
- Context and snippets. When you ask for a completion or chat about your code, Cursor sends the pieces it judges relevant (the open file, nearby code, your prompt) to the model. The more context a feature uses, the more of your code is transmitted.
- Codebase indexing / embeddings. Cursor can index your project to answer questions across the whole codebase. This involves computing embeddings of your code; what is stored and where depends on your settings and plan.
- Model providers in the middle. Because Cursor relies on external models, your code is processed by those providers under their terms, not only Cursor's.
Privacy Mode and what it actually means
The single most important setting for safety is Privacy Mode. According to Cursor's own documentation, when Privacy Mode is enabled, your code is not stored by Cursor and is not used to train models. That is a strong, useful guarantee — and it is the default expectation for serious work.
But it is important not to over-read it. Privacy Mode is about retention and training, not about keeping code on your machine. Even with Privacy Mode on, your code and prompts still have to be sent to the model providers at request time so a response can be generated. "Not stored" is real and valuable; it is not the same as "never transmitted." If your threat model requires that code never leaves your hardware at all, Privacy Mode alone does not deliver that.
Free vs Pro vs Business: what changes
Cursor's plans differ in features and limits, and the data handling differs in emphasis rather than turning into something exotic:
| Plan | Privacy Mode | Code stored / used for training | Admin & compliance controls |
|---|---|---|---|
| Free / Pro | Available (you enable it) | With Privacy Mode on: not stored, not trained on. With it off: some data may be retained to improve the product | Individual settings only |
| Business / Enterprise | Enforced for the whole team | Not stored, not used for training (Privacy Mode applies org-wide) | Centralised admin, SSO, org-wide policy; zero-data-retention with model providers is documented for these plans |
The practical takeaway: on Free and Pro, you are responsible for switching Privacy Mode on and keeping it on. On Business/Enterprise, an admin enforces it for everyone and gains controls that make the tool easier to govern — which is why organisations handling confidential code tend to standardise there.
The real risks
Cursor is not malware, and these risks are the ordinary ones of any cloud AI tool — but they are real:
- Proprietary or secret code sent to third parties. The defining risk: your source travels to external model providers. With Privacy Mode that data is not retained or trained on, but it is still processed by parties you have to trust.
- Secrets leaking through prompts or files. API keys, tokens, passwords and credentials sitting in code or pasted into chat can be transmitted along with the context. Keep them out.
- Trust in the model providers. You are relying on both Cursor and its upstream providers (Anthropic, OpenAI and others) to honour their stated handling — a reasonable but not zero-trust assumption.
- Extensions and MCP. Cursor supports extensions and Model Context Protocol servers that can read your code, hit external services, or take actions. A poorly chosen or malicious one expands your exposure well beyond Cursor itself.
How to use Cursor more safely
You can keep most of the benefit while sharply reducing the risk:
- Turn on Privacy Mode and confirm it stays on — on Free/Pro it is your responsibility.
- Never paste secrets. Keep API keys, tokens and credentials in environment variables and secret managers, not in code Cursor can read or in chat.
- Use a
.cursorignorefile to exclude sensitive files and folders (secrets, infra config, anything regulated) from indexing and context. - Prefer a Business/Enterprise plan if you need org-wide enforcement, admin controls and documented zero-data-retention for compliance.
- Audit extensions and MCP servers before trusting them; treat them as code that runs with access to your project.
- Go local for the most sensitive code. For trade secrets or regulated data, a locally run model leaves nothing to chance — see our guide to the best local LLM for coding. If you want options beyond Cursor, see Cursor alternatives, and to understand the extension/agent attack surface, read MCP security.
The honest verdict
Is Cursor AI safe? For the vast majority of users — everyday projects and most commercial work — Cursor is a reasonable choice when you enable Privacy Mode, keep secrets out, and use .cursorignore. Its documented stance is clear: with Privacy Mode on, your code is not stored or used for training. The caveat is equally clear: your code is still sent to third-party model providers to be processed, so for trade secrets, regulated data, or strict-confidentiality code, you should be cautious and lean on .cursorignore, a Business plan, or a locally run model. As with every AI tool, share as little as you can and keep the most sensitive material off the cloud. For the wider picture, see our guide to AI and data privacy and the companion piece is DeepSeek safe.
