Sentence Case Validator
Checks if a string starts with a capital letter and subsequent letters are lowercase (excluding proper nouns)
/^[A-Z][a-z]+(?: [a-z]+)*$/
by RegexBuilder
Time Format (HH:MM:SS)
Matches time in HH:MM:SS format (24-hour clock)
/^([01]\d|2[0-3]):([0-5]\d):([0-5]\d)$/
by RegexBuilder
Markdown Bold/Italic Extractor
Extracts text enclosed in Markdown bold (**) or italic (*) markers
/\*\*(.+?)\*\*|\*(.+?)\*/g
by RegexBuilder
Vowel Counter (at least 3 unique)
Matches strings containing at least three different vowels (a, e, i, o, u - case-insensitive)
/(?i)(?=.*a)(?=.*e)(?=.*i)(?=.*o)(?=.*u).*/g
by RegexBuilder
Currency Amount (USD) with commas
Matches US dollar amounts with optional dollar sign and commas
/^\$?(?:[1-9]\d{0,2}(?:,\d{3})*|0)(?:\.\d{2})?$/
by RegexBuilder
Image File Extension Extractor
Extracts common image file extensions (jpg, jpeg, png, gif)
/\.(jpg|jpeg|png|gif)\b/gi
by RegexBuilder
Markdown Link Extractor
Extracts links from Markdown text
/\[([^\]]+)\]$$([^)]+)$$/g
by RegexBuilder
IP Address Validator
Validates IPv4 addresses
/\b(?:(?: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]?)\b/g
by RegexBuilder
HTML Tag Extractor
Extracts HTML tags from text
/<([a-z]+)([^<]+)*(?:>(.*?)</\1>|\s+/>)/gi
by RegexBuilder
Credit Card Number
Matches 16-digit credit card numbers with optional separators
/(?:\d{4}[- ]?){3}\d{4}/g
by RegexBuilder
US Phone Number
Matches US phone numbers in various formats
/\d{3}-\d{3}-\d{4}|$$\d{3}$$\s?\d{3}-\d{4}|\d{3}\s\d{3}\s\d{4}/g
by RegexBuilder
URL Extractor
Extracts URLs from text
/https?://[\w.-]+\.\w+(/[\w./]*)?/g
by RegexBuilder
Strong Password Checker
Ensures password has uppercase, lowercase, number, and special character
/^(?=.*[A-Z])(?=.*[a-z])(?=.*\d)(?=.*[!@#$%^&*]).{8,}$/
by RegexBuilder