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Ctrl+K

PII Mask

Detect emails, phone numbers, IPs, card numbers, and tokens in logs or JSON and replace them in your browser. Nothing is sent to a server.

Input (log / text)
Detection types
Mask style
Result
Email: 0
Phone (JP): 0
IPv4: 0
IPv6: 0
Card number: 0
Token: 0
Masked output
Read Only

How to use

About this tool

Detects emails, JP phones, IPs, Luhn-valid card numbers, and token-like strings in logs/JSON and replaces them in the browser. Nothing is sent to a server.

How to use

Paste text (or insert the sample). Choose detection types and mask style; switch to JSON mode if needed. Copy the result into Issues/Slack/etc.

Options

Types: email / phone_jp / ipv4 / ipv6 / credit_card / token. Styles: type placeholders (default), fixed ***, dummy examples. Modes: Text/Log or JSON (string values only; Pretty optional).

Use cases

• Quick redact before pasting prod logs into Issues • Obfuscate API JSON before sharing • Strip secrets before incident or vendor handoff

How it works

Client-side regex/heuristics. Cards require Luhn. Names, addresses, and My Number are out of scope.

Privacy and data

Input is processed only in your browser; not sent or stored on a server. Not a DLP substitute; misses/false positives possible. No legal compliance guarantee.

FAQ

Q: Is this a full DLP tool?
A: No. It is a quick browser helper with pattern-based detection. It does not guarantee legal compliance (GDPR, etc.).
Q: Is my data uploaded?
A: No. Masking runs entirely in your browser. Nothing is sent to our servers.
Q: Why are Japanese names not masked?
A: v1 excludes personal names because NER/morphological analysis causes many false positives. That may come later as a separate task.
Q: Why was my card number not masked?
A: Only numbers that pass the Luhn check are masked, to reduce false positives on random digit sequences.