Utility Tool

Regex Test Notes

Try a JavaScript regular expression, preview matches and replacements, and turn the result into documentation notes.

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Pattern

FlagsReplacement

Purpose NoteSample Text

Matches

dev@example.com
security@example.org

Replacement Preview

Contact [email] or [email] for access.

Generated Documentation Notes

Purpose: Mask email addresses in support notes before sharing examples.
Pattern: /\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\b/gi
Sample matches: dev@example.com, security@example.org
Replacement preview: Contact [email] or [email] for access.
Review reminders:
- Add positive and negative examples before production use.
- Check performance on long input if the pattern uses nested repetition.
- Keep private data out of shared test samples.