Toolstack
Real-Time Match Highlighting • Groups & Replace

Online Regex Tester & Debugger

Evaluate regular expressions interactively with live highlight, capture group breakdowns, and ReDoS protection.

//g
2 matches found

Match Results & Groups

#1hello@toolstack.tools
Pos: 14
#2sales@domain.org
Pos: 39

Common Regex Patterns

Frequently Asked Questions

Clear, concise answers to common questions about Base64 decoding, encoding, and specifications.

A Regex Tester is an interactive developer tool that tests patterns against text in real time. It highlights matches, extracts capture groups, performs regex string replacements, and flags syntax errors.

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