Regex Pattern Library
Common regular expressions for validation and parsing
Email Address
Validates standard email addresses
Validation
Pattern:
^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$Examples:
URL
Matches HTTP and HTTPS URLs
Validation
Pattern:
^https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_\+.~#?&//=]*)$Examples:
✓
https://example.com✓
http://www.example.com/path?query=valuePhone Number (US)
US phone numbers with various formats
Validation
Pattern:
^(\+1)?\s?\(?\d{3}\)?[\s.-]?\d{3}[\s.-]?\d{4}$Examples:
✓
(555) 123-4567✓
+1 555-123-4567IPv4 Address
Validates IPv4 addresses
Network
Pattern:
^((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$Examples:
✓
192.168.1.1✓
255.255.255.0Hex Color
Matches hex color codes
Format
Pattern:
^#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3})$Examples:
✓
#FF5733✓
#FFFCredit Card (Visa)
Validates Visa credit card numbers
Validation
Pattern:
^4[0-9]{12}(?:[0-9]{3})?$Examples:
✓
4111111111111111✓
4012888888881881Date (YYYY-MM-DD)
ISO 8601 date format
Format
Pattern:
^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])$Examples:
✓
2024-01-15✓
2024-12-31Time (24-hour)
24-hour time format
Format
Pattern:
^([01]?[0-9]|2[0-3]):[0-5][0-9](:[0-5][0-9])?$Examples:
✓
14:30✓
09:05:30Username
Alphanumeric username, 3-16 chars
Validation
Pattern:
^[a-zA-Z0-9_-]{3,16}$Examples:
✓
user_name✓
User-123Strong Password
Min 8 chars, uppercase, lowercase, number, special char
Validation
Pattern:
^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[@$!%*?&])[A-Za-z\d@$!%*?&]{8,}$Examples:
✓
Password123!✓
Str0ng@PassUUID
Validates UUID v4 format
Format
Pattern:
^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$Examples:
✓
550e8400-e29b-41d4-a716-446655440000✓
123e4567-e89b-12d3-a456-426614174000HTML Tag
Matches HTML tags
Format
Pattern:
<([a-z]+)([^<]+)*(?:>(.*)<\/\1>|\s+\/>)Examples:
✓
<div>content</div>✓
<img src="image.jpg" />Regex Basics
^ - Start of string
$ - End of string
. - Any character
* - 0 or more
+ - 1 or more
? - 0 or 1
\d - Digit
\w - Word character
\s - Whitespace
[abc] - Character set
(x|y) - x or y
{n} - Exactly n times