USE CASE

Hide personal data before you paste text into ChatGPT or another AI

Before an email, a set of meeting notes, a support thread or a log goes into ChatGPT, Claude or Gemini, replace the addresses, phone numbers and customer names in it with something else. This is how that job goes with the Chrome extension Safe Privacy Mask.

Only the strings your rules match are replaced. It does not judge whether the text is fit to send to an AI, and it does not claim to find every confidential thing in it. It never sends anything for you either.

The text you want to ask about carries more than you need

Asking an AI to summarise something, or to rewrite an email, takes a certain amount of context. The same text also carries things the answer does not need at all.

You may only want to ask “make the email from Mr Tanaka easier to read”, while the original message still holds a full name, a company, an email address and a phone number.

Removing it by hand leaves more behind than you would think

In a short message you can delete them one at a time. In meeting notes, a long email or an error log, simply finding how many places they appear in is work.

  • Hunting by eye for every place the same name or number appears
  • Starting that check over each time you add another paragraph

And adding more information while you edit means checking the whole thing again.

The same job with Safe Privacy Mask

  1. 1

    Type or paste your text into the AI chat.

  2. 2

    Anything matching the rules you set is masked.

  3. 3

    tanaka@example.com becomes [Email address] — replaced right inside the input field.

  4. 4

    Read the masked text yourself.

  5. 5

    If it looks right, you send it to the AI yourself.

BEFORE

The contact is Taro Tanaka.

You can reach him at tanaka@example.com.

His phone number is 090-1234-5678.

AFTER

The contact is [Name].

You can reach him at [Email address].

His phone number is [Phone number].

Put the text in the field The major AI chats are covered as soon as you install it.
Matching strings are replaced The replacement happens inside the field; nothing has to be copied to another screen.
Read it, then send it yourself You check the masked text, and the send is your own action.

These are the shapes the presets look for.

Email addresses Phone numbers API keys & tokens IP addresses Credit card numbers Region-specific ID numbers Your own words & regular expressions

You choose when the replacement happens: as you type, when the field loses focus, on paste, or in the moment before the send. On sites other than the major AI chats, you register the fields you want covered.

What this looks like in practice

Asking an AI to improve an email

Hide the other person’s address and phone number, and ask about the wording alone.

Summarising notes from a meeting

Turn attendee names, companies and project names into [Contact], [Company] and [Project] first, then ask for the summary.

Asking about an error log or some code

Replace the API keys, tokens and IP addresses in the log before you paste it.

Translating a reply to a customer

Customer names and internal system names have no common format, so they go in as custom rules.

What Safe Privacy Mask does

  • Masks strings before they go to an AI
  • Detects email addresses, phone numbers, API keys and the like
  • Lets you register customer names, project names and other wording as your own rules
  • Shows you the result of the replacement inside the input field
  • Keeps the whole process inside your browser

What Safe Privacy Mask does not do

  • Judge whether something is fit to send to an AI
  • Detect every confidential thing without fail
  • Send the masked text automatically
  • Replace your organisation’s DLP or its information-handling rules

The point is not to keep you from using an AI. It is to hand over less of what the AI never needed — a small piece of preparation, done before you send.