Regex Common Patterns

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

https?://[^\s]+
# basic URL matching

^\d{3}-\d{3}-\d{4}$
# US phone format: 123-456-7890
^\(?\d{3}\)?[\s.-]?\d{3}[\s.-]?\d{4}$
# flexible phone format

^\d{4}-\d{2}-\d{2}$
# YYYY-MM-DD format
^\d{2}/\d{2}/\d{4}$
# MM/DD/YYYY format

^(?:[0-9]{1,3}\.){3}[0-9]{1,3}$
# basic IPv4

^#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3})$
# hex color code