Regex Tester
Test and debug regular expressions online with real-time matching and group highlighting. Free regex tester for JavaScript and Python.
^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$Validates email addresses
^https?:\/\/[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}(\/\S*)?$Matches URLs
^\+?1?[-.]?\(?\d{3}\)?[-.]?\d{3}[-.]?\d{4}$US phone numbers
^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$ISO date format
^([01]\d|2[0-3]):[0-5]\d$24-hour time
^((25[0-5]|2[0-4]\d|1\d{2}|[1-9]?\d)\.){3}(25[0-5]|2[0-4]\d|1\d{2}|[1-9]?\d)$IPv4 addresses
^#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})$Hex color codes
^\d{4}[- ]?\d{4}[- ]?\d{4}[- ]?\d{4}$Credit card numbers
^\d{5}(-\d{4})?$US ZIP codes
^\d{3}-\d{2}-\d{4}$Social Security Number
^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[@$!%*?&])[A-Za-z\d@$!%*?&]{8,}$Min 8 chars, mixed case, number, symbol
^[a-zA-Z0-9_]{3,16}$3-16 alphanumeric or underscore
^[a-z0-9]+(?:-[a-z0-9]+)*$URL-friendly slug
<([a-z]+)([^<]+)*(?:>(.*)|\/)(\/>|<\/\1>)Matches HTML tags
^\d+$Only digits
^[a-zA-Z]+$Only letters
How to Use Regex Tester
Open Regex Tester
Navigate to Regex Tester in your browser — no installation or sign-up required.
Enter your data
Type, paste, or upload the content you want to process into the input area.
Configure options
Adjust any available settings to customize the output to your needs.
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Frequently Asked Questions
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