Use AI without handing over your private life

Not long ago, asking an AI assistant for help mostly meant asking it general questions. Now people hand it their actual paperwork: a tenancy agreement they don't fully understand, a hospital discharge letter, a payslip that doesn't add up, a contract that needs a second opinion before it's signed. That's where AI is genuinely useful. It reads carefully, explains plainly and doesn't get tired.

It's also where many of us hesitate. Those documents are full of things we'd never post publicly: our full name and address, our date of birth, account numbers, ID numbers, the names of our family, clients or patients.

Two things we want at once

Most people want both. They want the help AI can give, and they don't want an AI service to know more about them than it needs to. Those wishes pull in opposite directions, and today people tend to settle the tension in one of three ways.

Some upload the document and hope for the best. Some give up and don't use AI for anything personal or work-related, missing out on help that could save them hours. And some try to clean the document up by hand — retyping it, deleting names, blacking out lines — which is slow and easy to get wrong, especially on a scanned page or a 40-page contract.

What happens to what you share

Once a document is pasted or uploaded into an AI chat, it lives on someone else's servers. Depending on the service and your settings, it may be kept in your chat history, reviewed to improve the service, or used to train future models. Even when a provider's policies are good, the data is out of your hands: it can be exposed in a breach, seen by someone who shares your account, or kept longer than you expected.

For work documents the stakes are higher. Lawyers, accountants, HR teams and clinicians handling other people's information often have professional or legal duties about where it goes. Pasting a client file into a chatbot can be a problem even if nothing bad ever happens to it.

The AI rarely needs the personal details

Here's the useful part: to summarise a lease, explain a medical letter or check a contract, an AI almost never needs to know who's involved. It needs the structure and the substance — what was agreed, the dates and amounts, who owes what to whom. The names, addresses and account numbers are what make the document sensitive, and they're usually the part the AI can do without.

That's what redaction does. It removes the identifying details and keeps the rest. Done well, you keep nearly all of the AI's usefulness and take on very little of the risk.

Redaction that keeps the meaning

Traditional redaction — a black bar over every name — works when you're sharing a document with a person who shouldn't see certain parts. For AI it falls short: if every person becomes a black box, the AI can't tell who said what to whom, and its answers turn vague.

So RedactGuru can replace each detail with a numbered label like [Name 1] or [Address 1] instead. The same person always gets the same label, even across several documents in a folder, so the AI can still follow the story. When it answers, you know exactly who [Name 1] is. The AI doesn't.

Why it has to happen on your computer

There's a catch with any tool that strips private details before you share: if the tool uploads your document to do it, you've only moved the problem. That's why RedactGuru finds and removes sensitive details entirely on your computer. It works with Wi‑Fi turned off, and it doesn't keep your documents or a record of what you redacted.

It also checks its own work. You review every highlight before anything is removed, and after export RedactGuru reads the finished file again to make sure nothing you removed can still be found. The redacted copy is flattened, so the original text isn't hiding under a box.

A habit worth keeping

We don't think the answer is to stop using AI, or to trust every service with everything. It's a simple habit: before a document leaves your computer, take out what doesn't need to go. RedactGuru is built to make that habit quick enough that you'll actually keep it.

You can try it free on documents up to 5 pages. Download RedactGuru for Mac and redact your next document before you share it.