Regex Tester
Test regular expressions in real time. Your text never leaves your browser.
Test Your Regex Pattern
What this tool does not do
- Uses JavaScript regex engine — some PCRE features may not be supported.
- Very large texts with complex patterns may slow down.
- Does not save or persist patterns between sessions.
How It Works
Enter a pattern
Type your regex pattern and toggle flags as needed.
Paste test text
See matches highlighted in real time as you type.
Review matches
Inspect match count, positions, and captured groups.
Frequently Asked Questions
How does the regex tester work?
Type your regular expression pattern and test text. Matches are highlighted in real time. You can set flags like global, case-insensitive, multiline, dotall, and unicode.
What regex flags are supported?
The tool supports g (global), i (case-insensitive), m (multiline), s (dotall), and u (unicode) flags. Toggle them on or off to see how they affect matching.
Can I see details about each match?
Yes. Below the test text, you can see a list of all matches with their position (index) and captured groups. The match count is also displayed.
Is my text uploaded to a server?
No. All processing happens entirely in your browser. Your text never leaves your device.