Regex Tester & Live Match Visualizer
Test regular expressions with real-time match highlighting, capture group details, and replace substitution preview.
| # | Index | Matched Text | Length | Capture Groups |
|---|---|---|---|---|
| 1 | 14 | hello@joytools.dev | 18 | None |
| 2 | 36 | support@company.org | 19 | None |
How do I use Regex Tester & Live Match Visualizer?
Enter or select a regular expression pattern in the Pattern input box.
Set desired regex flags (g, i, m, s, u).
Paste or type your test string into the Test String input area.
View real-time match highlights, match counts, and detailed match positions.
What features does Regex Tester & Live Match Visualizer offer?
Real-time regex evaluation as you type
Visual match highlighting with match index indicators
Instant 'No Match' and 'Syntax Error' explicit visual feedback
Regex Find & Replace substitution mode with 1-click copy
100% Client-side local execution in browser memory
Frequently Asked Questions about Regex Tester & Live Match Visualizer
Why does it say 'No Matches Found'?
If your pattern requires specific formats (e.g. an email pattern requiring an @ symbol and a domain like .com) and your test text doesn't match that format, JoyTools explicitly notifies you that 0 matches were found.
Does it support regex substitution / replacement?
Yes! Switch to 'Find & Replace' mode in the right control panel to test regex replace rules with $1, $2 capture group placeholders.
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