Online Regex Tester
Test regular expression patterns and flags against sample text in real time.
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About Free Online Regular Expression (Regex) Tester
Test and debug JavaScript regular expressions against sample text in real time with custom flags (g, i, m) and highlighted matches.
How to Use
- Enter your regular expression pattern and flags (such as
gfor global orifor case-insensitive). - Type or paste your test string below.
- View all matched substrings and total match count immediately.
Key Features & Benefits
- Instant syntax error feedback helps you fix invalid regex patterns fast.
- Great for testing email validators, URL extractors, phone patterns, and log parsers.
Frequently Asked Questions
What do the g and i regex flags mean?
The g flag finds all matches instead of stopping at the first one, and i makes the match case-insensitive.
The g flag finds all matches instead of stopping at the first one, and i makes the match case-insensitive.
Which regex flavor does this tester use?
It uses your browser's native JavaScript RegExp engine.
It uses your browser's native JavaScript RegExp engine.