What is pii-airlock?
When you paste text into an AI assistant, that text travels to the company running the AI. If it contains a customer's name, an email address, a phone number or a password, that data leaves your computer too.
pii-airlock is a small program that runs on your own computer and sits between you and the AI. Think of it as an airlock: personal details cannot pass through it in the clear.
How it works
- You write your question as usual.
- pii-airlock finds names, emails, phone numbers, bank numbers, secret keys and similar items.
- It swaps each one for a placeholder, for example
<PERSON_482913>. - The AI sees only placeholders and answers using them.
- pii-airlock swaps the originals back into the answer before you read it.
The same person always gets the same placeholder, so the AI can still follow who is who. You can read more in Placeholders explained.
What it is good for
- Asking an AI to draft or summarise something that mentions real people.
- Letting a coding assistant work in a project that contains customer data.
- Cleaning a file (text, CSV, JSON, Word, PDF) before you share it.
What it is not
- Not a guarantee. Detection is smart but not perfect. It can miss a name or flag a word that is not personal. Read Safety and limits before you rely on it for sensitive work.
- Not a cloud service. Nothing is uploaded to pii-airlock's authors. Detection runs on your machine.
- Not an AI itself. It does not answer questions. It only protects what you send to the AI you already use.
Two ways to use it
You pick one depending on the tool you use. Pick your setup helps you choose.
| The gateway | Hooks | |
|---|---|---|
| In plain words | A local address your AI app talks to instead of the provider | Guards built into Claude Code and Copilot |
| What it does | Swaps and restores automatically | Stops and warns you before personal data is sent |
| Best for | Chat apps, SDKs, Cursor, Codex, Aider | Claude Code and Copilot working on your files |