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Best Chrome Extensions to Hide Personal Data from ChatGPT (2026)

PiiBlocker Team

chatgptprivacychrome extensionscomparison

The best way to hide personal data from ChatGPT is a Chrome extension that detects it as you type and swaps it for placeholders before the message is sent. ChatGPT then works on [PERSON_A] and [EMAIL_A], and the real values never leave your browser. PiiBlocker does this for free on ChatGPT, Claude, Gemini, Perplexity, Grok, DeepSeek and Kimi, with all detection running locally. Every extension below runs locally too, so that is not where they differ. They differ in what the free version actually covers, whether you get your real data back in the reply, what happens when the extension breaks, and whether a team can deploy it. On those points PiiBlocker gives away what most of the others charge for.

Disclosure: PiiBlocker is our product. We have tried to describe the alternatives fairly, and we link to each so you can check for yourself.

Where PiiBlocker is different

Five things set PiiBlocker apart from the other extensions in this comparison, checked against each one's listing and website on October 2, 2026.

  • The whole product is free. 15 or more types on all seven sites, with no usage limits and no account. Caviard's free plan stops at 10 protected values per document. PrivacyScrubber's covers 5 core categories. ChatWall's free tier leaves out card numbers, Social Security numbers and API keys.
  • Your real data comes back on its own. Placeholders in ChatGPT's reply are swapped back automatically, in the normal chat box. PrivacyScrubber and PasteSecure restore on click, and ChatWall restores inside its own window.
  • Masking matches the risk. Card numbers, Social Security numbers and API keys are masked automatically. Names, addresses and emails wait for one click from you.
  • It fails safe. If PiiBlocker cannot check a message, it blocks the send instead of letting it through, and it runs self-checks on every supported site.
  • It is the most installed. 492 Chrome users, more than any other extension here.

What to look for

Five things separate a useful extension from a risky one.

  • What the free version covers. Many extensions are free to install and paid to use properly. Check which data types and sites are in the free tier, and whether there is a cap.
  • Network calls. A local tool should make none while it works. You can check in Chrome DevTools, Network tab.
  • Whether you see it before it is sent. A confirmation step lets you catch misses and false positives.
  • Whether the reply makes sense. Good tools swap the real values back into ChatGPT's answer on your screen, without an extra click.
  • What happens when it breaks. ChatGPT changes its page often. An extension that stops working silently lets your data through without telling you.

The extensions compared

Extension Chrome users Free tier covers Real data back in reply For teams
PiiBlocker 492 15+ types, 7 sites, no limits Automatic, in the chat box Managed deployment, admin dashboard, $6.99 per seat/month billed annually
Caviard 342 10 values per document, ChatGPT and DeepSeek Not stated Lifetime licence per device; custom plans via sales
ChatWall 105 Names, contact details, places, dates; cards, IDs and API keys are paid Automatic, in its own window Plans by device, from $19/month for 10
PrivacyScrubber 99 5 core categories On click $99/month flat
PasteSecure 69 Not published On click Not published
Privacy Protector for ChatGPT 55 Words you add to its dictionary Yes None

All six run locally in the browser. User counts, prices and free tiers are from each extension's Chrome Web Store listing and website on October 2, 2026. Listings change, so check them before you install.

PiiBlocker

PiiBlocker highlights personal data as you type in ChatGPT and six other AI chats. Before the message goes, a dialog shows what it found. Critical items such as card numbers, Social Security numbers and API keys are redacted automatically; names, addresses and emails you confirm with one click. ChatGPT receives placeholders, and the reply is unmasked on your screen.

It detects 15 or more types, including UK National Insurance numbers, dates of birth, salaries and medical conditions. A right-click option masks anything it missed, and a personal dictionary learns names and terms specific to you. The free version has no account, no usage limits and makes no network calls. An enterprise tier adds Group Policy deployment and an admin dashboard.

ChatGPT changes its page layout often, and that is when masking extensions break. PiiBlocker checks its own protection on every supported site, and if it ever cannot inspect a message, it blocks the send rather than letting unchecked text through. For teams, IT can push it through Group Policy, MDM or the Google Admin Console and lock it on, at a published per-seat price with no sales call.

Best for: anyone who wants full protection without paying for it, and teams that need it locked on across every machine.

Caviard

An extension with a free tier, focused on redacting personal information in ChatGPT, Claude, Gemini and DeepSeek, running locally. Simple to set up. Its pricing page lists the free plan for ChatGPT and DeepSeek, with a one-time lifetime licence for unlimited redaction.

Best for: occasional ChatGPT or DeepSeek users who mask a handful of values at a time.

ChatWall

A local anonymisation extension with a European and GDPR focus. You type in a ChatWall window that the chat site's own scripts cannot read, and replies are restored in the same window. Card numbers, IBANs, ID numbers and API keys are masked only on paid plans.

Best for: users who want their typing kept away from the chat site's scripts, and will pay to mask financial and identity data.

PrivacyScrubber

A browser-based redaction tool with a Chrome extension and a web version for documents. It publishes a lot of guidance content and has vertical pages for legal and other professions. The extension supports 12 sites, including Notion, Slack and Zendesk, and reads screenshots and PDFs locally. The free version covers 5 core categories.

Best for: people who want one tool for prompts and files, and will pay for the full set of data types.

PasteSecure

A local extension that checks what you type or paste into AI tools, email and other web apps, with a paid tier.

Best for: people who want one tool across AI chats, email and support tickets.

Privacy Protector for ChatGPT

A free, ChatGPT-only extension. It replaces only the words you add to its dictionary yourself, with no automatic detection. Check the listing's last-updated date before installing; ChatGPT changes its page layout often, and an extension that has not kept up can silently stop working. At the time of writing, the listing was last updated on July 2, 2025.

Best for: ChatGPT-only users who want something minimal.

When an extension is not enough

An extension protects what you type into a supported chat in Chrome. It does not cover the ChatGPT desktop or mobile apps, other browsers, or files you upload. If your organisation needs policy enforcement across every device and app, that is a data loss prevention product, such as Microsoft Purview, Nightfall or Strac, usually alongside a browser extension rather than instead of one. We compare the two approaches in DLP vs. browser extensions for AI chatbots.

Turning off "Improve the model for everyone" in ChatGPT's settings is worth doing, but it is not the same thing. It changes what OpenAI does with your data after it arrives. Hiding the data before it is sent means there is nothing to change. For what ChatGPT keeps once it has your data, see what ChatGPT remembers about you, and how to check.

Frequently asked questions

Which of these extensions is free without limits? PiiBlocker's free version detects 15 or more types on all seven supported sites with no usage limits and no account. Caviard's free plan stops at 10 protected values per document, PrivacyScrubber's covers 5 core categories, and ChatWall's free tier leaves out card numbers, Social Security numbers and API keys.

Can I hide personal data from ChatGPT without an extension? Yes, by removing it by hand before you paste. It works, but it is slow and easy to miss things like a phone number in an email signature.

Does ChatGPT's temporary chat hide my personal data? No. Temporary chats are not saved to your history, but the text is still sent to OpenAI and processed.

Are these extensions safe to install? Check three things: that detection runs locally, that the extension makes no network calls while you use it, and that it only asks for access to the AI sites it supports.

Does PiiBlocker work in the ChatGPT desktop app? No. It works in Chrome on chatgpt.com and the six other supported sites.

Is PiiBlocker free? Yes. Core detection and masking is free with no account and no usage limits.

Sources

Install PiiBlocker free from the Chrome Web Store, or see every supported site and detected data type at piiblock.com.