A fast, browser-based Regular Expression tester. Write your Regex pattern at the top and paste your test text below. Real-time highlighting will display the matched regions instantly.
Build and debug regular expressions with this free online regex tester. Type your pattern, enter a test string, and see live highlighted matches as you type. The tool supports JavaScript regex syntax with configurable flags including global, case-insensitive, multiline, and dotAll — perfect for crafting patterns for validation, parsing, and text extraction.
Enter your regex pattern in the expression field, toggle the flags you need, and paste your test string in the left panel. Matches are highlighted instantly in the result panel with alternating colors to distinguish capture groups. Click Copy Matches to grab all matched text, or Clear All to start fresh.
All matching runs entirely in your browser — your patterns and test data stay on your device. No registration required, no restrictions, and completely free. Keep this regex tester bookmarked for fast, private regular expression testing online.
