Data Anonymizer

About the Data Anonymizer

This tool masks common sensitive values in logs, request payloads and config files so you can paste them into a ticket, chat or bug report. Each match is replaced with a placeholder token, and a table shows how many values were masked in each category:

• JSON Web Tokens (three base64url segments starting with eyJ) become [JWT]
• email addresses become [email]
• UUIDs in the 8-4-4-4-12 hex form become [uuid]
• IPv4 addresses with octets 0 to 255 become [ip]
• IPv6 addresses written in the full 8-group form become [ipv6]
• card numbers of 13 to 19 digits, with optional spaces or dashes, that pass the Luhn checksum become [card]

Masking runs entirely in your browser; nothing is sent to the server. The Anonymize switch in the sidebar applies the same masking to text shown on every page, which helps when screen sharing.

How to use it

1. Paste text into the input, or click Load sample.
2. Review the masked output and the per-category counts.
3. Copy the masked text or download it as anonymized.txt.

Examples

• Mask a log line: the email and IPv4 address are replaced.
• Mask a card number and session ID: the Luhn-valid test card becomes [card] and the UUID becomes [uuid].

Common questions

Why wasn't a long number masked as a card?

Only digit sequences that pass the Luhn check are masked, so order IDs and timestamps usually stay intact.

Is the masking reversible?

No. Every match is replaced by the same fixed token, so masked output can't be turned back into the original values.

What does it not catch?

Anything outside the six categories: names, phone numbers, street addresses, passwords, and API keys that aren't JWTs. Compressed IPv6 addresses such as 2001:db8::1 aren't matched either. Review the output before you share it.

Related tools

• JWT Decoder: inspect a token before you mask it.
• Test Data Generator: create fake emails and IDs instead of using real ones.
• Text Diff Checker: compare the original and masked text.