Email Address

Contact
^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$

Matches standard email format, supports international domains

Test Examples: ✓ test@example.com ✗ test@.com

Phone Number

Contact
^1[3-9]\d{9}$

Matches Chinese mainland phone numbers

Test Examples: ✓ 13812345678 ✗ 12812345678

ID Card

Identity
^\d{17}[\dXx]$

Matches 18-digit ID card numbers, supports X ending

Test Examples: ✓ 110101199001011234 ✗ 11010119900101123

IP Address

Network
^(?:(?: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]?)$

Matches IPv4 address format

Test Examples: ✓ 192.168.1.1 ✗ 256.1.1.1

URL Link

Network
^https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_\+.~#?&//=]*)$

Matches HTTP/HTTPS links

Test Examples: ✓ https://www.example.com ✗ www.example

Date Format

Format
^\d{4}-\d{2}-\d{2}$

Matches YYYY-MM-DD format date

Test Examples: ✓ 2025-10-21 ✗ 2025-10-1

Time Format

Format
^([01]?[0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9]$

Matches HH:MM:SS format time

Test Examples: ✓ 23:59:59 ✗ 24:00:00

Chinese Characters

Text
[\u4e00-\u9fa5]

Matches Chinese characters

Test Examples: ✓ 你好世界 ✗ hello world

Numbers and Letters

Text
^[a-zA-Z0-9]+$

Matches strings containing only numbers and letters

Test Examples: ✓ abc123 ✗ abc-123