Match nth occurence of the patterns in the inner parenthesis. Put nth that you want to match in the curly braces (here, {3}).

Validates Credit Card Numbers of different type. Supports Visa, MasterCard, American Express, Diners Club, Discover and JCB Taken from http://www.regular-expressions.info/creditcard.html If you want to support only a particular type, customise it based on following....

Validate IPv4 addresses using PCRE's recursion patterns. A shorter but less efficient alternative to https://regex101.com/r/wZ6oY5/1

use this to get value of any side of an equation. You can combine this with https://regex101.com/r/fH5kJ1/1

Detects valid Roman numerals (up to 3999), and splits into 4 capture groups: thousands, hundreds, tens, and units.

Text output produced by reading the QR code present on patient stickers created by Epic (R) medical record software

This regex matches against season and series names

Finds Typescript's reference path syntax.

Pull zip download ID from default links. Works with datadelivery and datadelivery1

Usage: "40%".replace(/\b([\d\.]+)mkb%/ig, '$1')

Validates hexadecimal color codes based on the following rule set: Optionally starting with a hash. 3 or 6 characters in length. Using the [0-9a-f] character set.

Valid and Invalid emails

([!-\~]aeiou)