TinyToolHub
Regex Tester
Test regular expressions and find pattern matches
Dev Tool
Regular Expression Pattern
Flags
Test Text
About Regex Tester
The Regex Tester is a fast, privacy-first way to develop and debug regular expressions directly in your browser. Enter a pattern, toggle flags, paste sample text, and instantly see matches highlighted in real time.
Frequently Asked Questions
What is a regular expression?
A regular expression (regex) is a sequence of characters that defines a search pattern used for matching text.
How do the flags work?
Flags modify how the pattern is applied—e.g. global (g) finds all matches, ignore-case (i) makes matching case-insensitive, etc.
Is my data sent anywhere?
No. All processing happens entirely in your browser. Nothing is uploaded.
Why doesn’t my pattern match?
Make sure you’ve escaped special characters correctly and enabled the right flags.
Can I debug capture groups?
Yes. Group values are listed under each match so you can inspect them easily.
Where can I learn more about regex?
Check out MDN’s regular expressions guide.