Regex Tester
Test JavaScript regular expressions in real time — highlight matches, inspect capture groups, and try common patterns.
The quick brown fox jumps over the lazy dog
foo@example.com
https://glot.so
How to Use the Regex Tester
- 1
Enter your regular expression
Type your regex pattern in the expression field. Use the flag toggles (g, i, m, s) to enable global, case-insensitive, multiline, or dotAll matching.
- 2
Add your test string
Paste the text you want to test against. You can also click a quick pattern (email, URL, phone, etc.) to load a common regex instantly.
- 3
Review highlighted matches
Matching text is highlighted in real time. Below the test string, you'll see each match with its position, length, and captured groups — ideal for debugging complex patterns.
What is a Regex Tester?
A regex tester (regular expression tester) lets you write and test patterns to search, match, and extract text. This free online tool supports JavaScript regex syntax with flags: global (g), case-insensitive (i), multiline (m), and dotAll (s). Instantly see highlighted matches, capture groups, and match positions — no setup required.