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Published: June 2026•By Web Util Slyce Team•8 min read
Regex Examples — Common Regular Expression Patterns
A collection of practical regex (regular expression) examples for common validation and matching tasks. Test any pattern interactively with our Regex Tester or generate patterns using AI Regex Generator.
Email Validation
/^[\w.-]+@[\w.-]+\.\w{2,}$/✓ Matches
- john@example.com
- jane.doe@company.co.uk
- user+tag@domain.org
✗ Does Not Match
- not-an-email
- @missing.com
- user@.com
URL Matching
/https?:\/\/[\w.-]+(:\d+)?(\/[\w./-]*)?(\?[\w&=.-]*)?(#[\w-]*)?/✓ Matches
- https://example.com
- http://site.com/page?id=1#section
- https://api.example.com:8080/v1/users
✗ Does Not Match
- ftp://file.com
- just-a-string
- www.example.com
Phone Number (US)
/\(?\d{3}\)?[-.\s]?\d{3}[-.\s]?\d{4}/✓ Matches
- (555) 123-4567
- 555-123-4567
- 555.123.4567
- 5551234567
✗ Does Not Match
- 12345
- 555-1234
- +1-555-123-4567
Strong Password Validation
/^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[!@#$%^&*]).{8,}$/✓ Matches
- P@ssw0rd!
- Secure#1Pass
- MyStr0ng!Pass
✗ Does Not Match
- weak
- onlylowercase1!
- NOLOWERCAPS1!
IPv4 Address
/^(?:(?:25[0-5]|2[0-4]\d|[01]?\d\d?)\.){3}(?:25[0-5]|2[0-4]\d|[01]?\d\d?)$/✓ Matches
- 192.168.1.1
- 10.0.0.255
- 8.8.8.8
✗ Does Not Match
- 256.1.2.3
- 192.168.1
- abc.def.ghi.jkl
Date (ISO 8601)
/^\d{4}-\d{2}-\d{2}(T\d{2}:\d{2}:\d{2}(\.\d+)?(Z|[+-]\d{2}:\d{2})?)?$/✓ Matches
- 2026-06-01
- 2026-06-01T14:30:00Z
- 2026-06-01T10:00:00+05:00
✗ Does Not Match
- 01/06/2026
- June 1, 2026
- 2026-13-01
Hexadecimal Color Code
/^#([0-9a-fA-F]{3}|[0-9a-fA-F]{6})$/✓ Matches
- #fff
- #000000
- #FF5733
- #abc
✗ Does Not Match
- #1234567
- FF5733
- #xyz
- rgb(255,0,0)
Username Validation
/^[a-zA-Z][a-zA-Z0-9_]{2,15}$/✓ Matches
- john_doe
- Alice123
- dev_guy
✗ Does Not Match
- ab
- 1starts_with_digit
- too_long_username_here
- spaces not allowed
Extract All Hashtags
/#[a-zA-Z]\w*/g✓ Matches
- #javascript
- #regex
- #100DaysOfCode
✗ Does Not Match
- #123
- not a tag
- ##double
Regex Quick Reference
| Pattern | Description |
|---|---|
| \d | Any digit (0-9) |
| \w | Word character (a-z, A-Z, 0-9, _) |
| \s | Whitespace (space, tab, newline) |
| . | Any single character (except newline) |
| * | Zero or more of the preceding character |
| + | One or more of the preceding character |
| ? | Zero or one (optional) of the preceding |
| {n,m} | Between n and m occurrences |
| ^ | Start of string anchor |
| $ | End of string anchor |
| (...) | Capturing group |
| (?:...) | Non-capturing group |
| | | Alternation (OR) |
| [abc] | Character class (a, b, or c) |
| [^abc] | Negated character class (not a, b, or c) |