Free Utility
100% Secure
Regex Tester & Debugger
Test and debug JavaScript regular expressions in real-time with match highlighting, capture groups, replace mode, and a cheat sheet.
Regular Expression
//
Test String
Match Results(8 matches)
Hello World! This is a Regex Tester. Try matching Words that start with Capital letters.
#1
"Hello"index 0
#2
"World"index 6
#3
"This"index 13
#4
"Regex"index 23
#5
"Tester"index 29
#6
"Try"index 37
#7
"Words"index 50
#8
"Capital"index 72
Replace
Overview
What this tool does
Test and debug JavaScript regular expressions in real-time with visual match highlighting and substitution.
100% private in-browser processing. Zero cloud uploads.
Tutorial
How to use it
- 1Type or paste your regular expression pattern and flags.
- 2Enter your test string to see matches highlighted instantly.
- 3Inspect capture groups or use the Replace tool to format matches.
- 4Reference the built-in regex cheat sheet for syntax help.
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