The AI sees [PERSON_1]. You see your client.
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Works with ChatGPT, Claude, Copilot and any other AI tool.
Nonimo keeps client data out of the AI wherever you use it: any app, Chrome and Safari, your files, your IDs.
Nonimo sits in the centre showing a short example with its client data redacted, with four cards around it: any app with one key, ChatGPT, Claude and Gemini in Chrome and Safari, Word, Excel and PDF files, and ID documents such as passports.
Select text in an email, Word or Teams, press one key, and client data becomes [PERSON_1].
See how it works →Word, Excel, PDF and more: the client data inside is redacted before the file goes to an AI.
Redacting files →The extension redacts pastes into ChatGPT, Claude or Gemini, with the Nonimo app on Mac or Windows.
See the extension →Cover chosen fields on a passport or driving licence and watermark it with what it's for and the month.
Redacting IDs →Trained by Nonimo to spot personal data even when nothing flags it: a first name on its own, a firm mentioned halfway through a sentence.
What it picks up →If your company connects its own apps to AI through an API, Nonimo Gateway redacts the data on your servers before every request goes out.
Explore the Gateway →[nonimo]
Email · Outlook
What you wrote
Hi Oliver Brannoxley, your refund on ref. INV-2026-0417 went out this morning.
What the AI receives
Hi [PERSON_1], your refund on ref. [REFERENCE_1] went out this morning.
clients.xlsx · row 14
What you wrote
Client: Harriet Quellanby · Email: harriet.quellanby@example.com · Ref.: INV-2026-0593
What the AI receives
Client: [PERSON_1] · Email: [EMAIL_1] · Ref.: [REFERENCE_1]
Nonimo's own model
What you wrote
Quick update: Rowan Telfair rang about the Hollin & Marsh renewal and wants an answer by Friday.
What the AI receives
Quick update: [PERSON_1] rang about the [COMPANY_1] renewal and wants an answer by Friday.
Nonimo Gateway
What you wrote
Draft a reply to Imogen Carraway about her delivery and send it to imogen.carraway@example.com.
What the AI receives
Draft a reply to [PERSON_1] about her delivery and send it to [EMAIL_1].
Passport · data page
The AI never sees your dataReversibleNo cloud involved
Our own model
It reads the whole sentence the way a colleague would, and catches your clients' personal details before they leave your computer.
Attached is the agreement between Felix Ardenmoor and Brackwater Logistics, with his passport number X0000000. Could you look it over?
Attached is the agreement between [PERSON_1] and [COMPANY_1], with his passport number [PASSPORT_1]. Could you look it over?
Not someone else's model with our name on it. We trained it ourselves, for one job only.
It recognises a person or a business even without ‘Mr’, ‘Ms’ or ‘Ltd’ to give it away.
It works on your own computer, so your text never passes through Nonimo's servers.
Five sample documents: what you write, and what the AI actually receives.
More useful than anonymisation: in a second, with one key, Nonimo swaps names, Social Security, Medicare and PPS numbers, bank details and addresses for labels on your computer before they reach ChatGPT, Claude or Copilot, then puts every one of them back in the reply. Below are five example documents to try it on.
When someone asks for a copy of your passport or ID card, Nonimo redacts what they don't need and you send it with peace of mind, without uploading it anywhere.
Click or tap a bar to show what's under it
Some copies have to be complete. For those, Nonimo stamps what the copy is for and the month, so it is much harder to reuse for anything else.
For teams
IT rolls it out to every desk in one go, and you get a signed report showing how much was redacted, by category.
IT pushes it to Chrome on every company computer, from the admin console it already uses. Nobody has to remember to switch it on.
The app keeps a tally, on your own computer, of how many details of each kind it has redacted. You can download a PDF signed by Nonimo for any period you choose.
The desktop app runs on Mac and Windows. The browser extension installs in Chrome through enterprise policy, so your IT team can deploy it to every workstation from its usual management console.
Each computer can produce a digitally signed usage report showing how many names, documents, account numbers or addresses were redacted over a given period. The text and the data themselves are never stored. Whoever receives the report can check at nonimo.ai that Nonimo issued it and that it has not been altered.
For in-house applications that call AI through an API, there is Nonimo Gateway, which runs on your own servers.
Nonimo pseudonymises names and identifiers on your computer before the text reaches the AI, and puts them back in the reply. That is pseudonymisation, a safeguard the GDPR itself names: the AI provider sees placeholders, not your client.
The AI sees only the redacted version. Your text is redacted on your computer and doesn't reach Nonimo. More on the security page.
Copy the AI's answer and every label turns back into the real detail.
Nationality, ethnicity or language is often the whole point: in an asylum claim, it is the case. Nonimo redacts the person, not the question.
You see everything: each redacted detail is marked on screen, and one click undoes it.
[ADDRESS_1] [BIRTH_DATE_1] [COMPANY_1] [PHONE_1] [EMAIL_1] [DNI_1] [CARD_1] [PERSON_1] [TFN_1] One page for each profession: the identifiers in its paperwork, what Nonimo redacts before anything reaches an AI tool, and why.
What people ask before they install it: pseudonymisation versus anonymisation, the GDPR, documents, the word limit and where your text goes.
Nonimo is a desktop app for Mac and Windows that masks client data before it reaches ChatGPT or any other AI. On your computer, names and ID numbers become labels such as [PERSON_1], and the real details go back in when you copy the reply.
Nonimo keeps client data away from AI tools. It redacts selected text in any app with one key, what you paste into ChatGPT, Claude and Gemini, and Word, Excel and PDF files. It also covers the fields you choose on ID documents.
Nonimo is a desktop app for Mac and Windows that redacts personal data before you paste it into ChatGPT. Select the text and press one key: names, ID numbers and IBANs come back as labels, and your clients' data stays on your computer.
With the Nonimo app, your text is redacted on your computer and doesn't reach Nonimo. What you paste into the AI tool is the redacted version. More on the security page at nonimo.ai.
Under the GDPR, what Nonimo does is pseudonymisation. Personal data becomes labels on your computer, and because the table that restores the real values stays with you, the redacted text is still personal data for you.
Yes, Nonimo helps a firm meet its GDPR obligations. It applies pseudonymisation, a technical measure named in Articles 25 and 32(1)(a), and cuts what reaches the AI provider. The firm still needs a lawful basis, a processing contract and clear information for its clients.
Nonimo works with every AI tool, because it connects to none of them. It works on the text you select on your own computer before you paste it, so it behaves the same with ChatGPT, Claude, Copilot, Gemini or any other.
Yes, the Nonimo extension works in ChatGPT, Claude and Gemini, together with the Nonimo app on your Mac or Windows PC. On Chrome and Edge, you install it from the Chrome Web Store; on Safari, it's built into the Nonimo app for Mac.
Yes, Nonimo's online ID-document tool lets you cover the fields you choose on your passport and add a watermark. It also handles ID cards and driving licences, and runs in your browser, so your document is read and covered on your own computer.
Nonimo has a Free plan that redacts up to 100,000 words a month, with no credit card and no account. Personal and Team remove the cap for US$13.90 a month or US$139 a year; Team costs the same per person.