Regular Expressions 101

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Community Patterns

107

ECMAScript/JavaScript trim

ECMAScript (JavaScript)
Trim leading and trailing whitespace from a string.
Submitted by fp - 11 years ago (Last modified 2 months ago)
11

html color match: transparent, #fff, #123456, rgb, rgba, hsl, hsla

ECMAScript (JavaScript)
This may be useful or not to test whether a given string is a valid (more or less) html color value. It matches color values such as: #123 - short hex color value #123456 - hex color value rgb(255,255,0) - rgb color value rgba(255,255,0,1.0) - rgba color value hsl(360,100%,100%) - hsl color value...
Submitted by grouch - 10 years ago
35

Google like regex

ECMAScript (JavaScript)
Attempts to mimic Google search box behavior, returning an array with the separated search strings (that keep the +/- indicator for following operations)
Submitted by mettjus - 11 years ago
22

UK Postcode Checker

PCRE (PHP <7.3)
Checks for valid UK/British postcodes. There was another on here that had for some reason been upvoted, but it was actually incorrect as it worked on none of my valid own postcodes! Namely that it assumed two letters and a number (BS3) when you can have variations (M20). Allows for an optional spac...
Submitted by MaffooBristol - 10 years ago
4

For Auto RTFs

PCRE (PHP <7.3)
no description available
Submitted by Dan Bloomquist - 12 years ago
4

outer Parentheses

PCRE (PHP <7.3)
Finds the outermost pair of parentheses. Compatible with any amount of nesting
Submitted by Jonas Gerneth - 11 years ago
4

Command handling

PCRE (PHP <7.3)
Handles commands like in CMD
Submitted by anonymous - 10 years ago
4

parsing a numeric strings with backslash using regexp

PCRE (PHP <7.3)
no description available
Submitted by A.K. Asik - 10 years ago
4

uri parser

PCRE (PHP <7.3)
no description available
Submitted by anonymous - 10 years ago
4

Match nth occurence of pattern

PCRE (PHP <7.3)
Match nth occurence of the patterns in the inner parenthesis. Put nth that you want to match in the curly braces (here, {3}).
Submitted by Alex Hall - 10 years ago
4

Equation matching (without equal)

Python
use this to get value of any side of an equation. You can combine this with https://regex101.com/r/fH5kJ1/1
Submitted by Kerosene2000 - 9 years ago
4

Roman numeral detector

PCRE (PHP <7.3)
Detects valid Roman numerals (up to 3999), and splits into 4 capture groups: thousands, hundreds, tens, and units.
Submitted by Terence Linnell - 9 years ago
4

Epic EHR Sticker QR code patient information

PCRE (PHP <7.3)
Text output produced by reading the QR code present on patient stickers created by Epic (R) medical record software
Submitted by MeWa - 9 years ago
4

TV series season and episode names

PCRE (PHP <7.3)
This regex matches against season and series names
Submitted by mikey - 9 years ago
4

Typescript - /// <reference path="..."/> Expression

ECMAScript (JavaScript)
Finds Typescript's reference path syntax.
Submitted by Lovelidge, Shawn - 9 years ago
4

Remove common numeric suffixes (eg: 40m, 60%)

PCRE (PHP <7.3)
Usage: "40%".replace(/\b([\d\.]+)mkb%/ig, '$1')
Submitted by anonymous - 9 years ago
4

Validate hex color

PCRE (PHP <7.3)
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.
Submitted by Nathaniel Blackburn - 9 years ago
4

Jeff Test

PCRE (PHP <7.3)
Valid and Invalid emails
Submitted by anonymous - 9 years ago
4

JWT Validation

PCRE (PHP <7.3)
Validate a Json Web Token (JWT).
Submitted by Erik Maas - 9 years ago
4

kenteken validator

PCRE (PHP <7.3)
validator voor kenteken vb: 11-AA-BB
Submitted by Senne Root - 9 years ago
1...34567...901

Community Library Entry

10

Regular Expression
ECMAScript (JavaScript)

/
^[a-z](?:[-a-z0-9\+\.])*:(?:\/\/(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~!\$&'\(\)\*\+,;=:\xA0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|[\uD800-\uD83E\uD840-\uD87E\uD880-\uD8BE\uD8C0-\uD8FE\uD900-\uD93E\uD940-\uD97E\uD980-\uD9BE\uD9C0-\uD9FE\uDA00-\uDA3E\uDA40-\uDA7E\uDA80-\uDABE\uDAC0-\uDAFE\uDB00-\uDB3E\uDB44-\uDB7E][\uDC00-\uDFFF]|[\uD83F\uD87F\uD8BF\uD8FF\uD93F\uD97F\uD9BF\uD9FF\uDA3F\uDA7F\uDABF\uDAFF\uDB3F\uDB7F][\uDC00-\uDFFD])*@)?(?:\[(?:(?:(?:[0-9a-f]{1,4}:){6}(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|::(?:[0-9a-f]{1,4}:){5}(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:[0-9a-f]{1,4})?::(?:[0-9a-f]{1,4}:){4}(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:[0-9a-f]{1,4}:[0-9a-f]{1,4})?::(?:[0-9a-f]{1,4}:){3}(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:(?:[0-9a-f]{1,4}:){0,2}[0-9a-f]{1,4})?::(?:[0-9a-f]{1,4}:){2}(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:(?:[0-9a-f]{1,4}:){0,3}[0-9a-f]{1,4})?::[0-9a-f]{1,4}:(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:(?:[0-9a-f]{1,4}:){0,4}[0-9a-f]{1,4})?::(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:(?:[0-9a-f]{1,4}:){0,5}[0-9a-f]{1,4})?::[0-9a-f]{1,4}|(?:(?:[0-9a-f]{1,4}:){0,6}[0-9a-f]{1,4})?::)|v[0-9a-f]+[-a-z0-9\._~!\$&'\(\)\*\+,;=:]+)\]|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3}|(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~!\$&'\(\)\*\+,;=@\xA0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|[\uD800-\uD83E\uD840-\uD87E\uD880-\uD8BE\uD8C0-\uD8FE\uD900-\uD93E\uD940-\uD97E\uD980-\uD9BE\uD9C0-\uD9FE\uDA00-\uDA3E\uDA40-\uDA7E\uDA80-\uDABE\uDAC0-\uDAFE\uDB00-\uDB3E\uDB44-\uDB7E][\uDC00-\uDFFF]|[\uD83F\uD87F\uD8BF\uD8FF\uD93F\uD97F\uD9BF\uD9FF\uDA3F\uDA7F\uDABF\uDAFF\uDB3F\uDB7F][\uDC00-\uDFFD])*)(?::[0-9]*)?(?:\/(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~!\$&'\(\)\*\+,;=:@\xA0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|[\uD800-\uD83E\uD840-\uD87E\uD880-\uD8BE\uD8C0-\uD8FE\uD900-\uD93E\uD940-\uD97E\uD980-\uD9BE\uD9C0-\uD9FE\uDA00-\uDA3E\uDA40-\uDA7E\uDA80-\uDABE\uDAC0-\uDAFE\uDB00-\uDB3E\uDB44-\uDB7E][\uDC00-\uDFFF]|[\uD83F\uD87F\uD8BF\uD8FF\uD93F\uD97F\uD9BF\uD9FF\uDA3F\uDA7F\uDABF\uDAFF\uDB3F\uDB7F][\uDC00-\uDFFD]))*)*|\/(?:(?:(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~!\$&'\(\)\*\+,;=:@\xA0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|[\uD800-\uD83E\uD840-\uD87E\uD880-\uD8BE\uD8C0-\uD8FE\uD900-\uD93E\uD940-\uD97E\uD980-\uD9BE\uD9C0-\uD9FE\uDA00-\uDA3E\uDA40-\uDA7E\uDA80-\uDABE\uDAC0-\uDAFE\uDB00-\uDB3E\uDB44-\uDB7E][\uDC00-\uDFFF]|[\uD83F\uD87F\uD8BF\uD8FF\uD93F\uD97F\uD9BF\uD9FF\uDA3F\uDA7F\uDABF\uDAFF\uDB3F\uDB7F][\uDC00-\uDFFD]))+)(?:\/(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~!\$&'\(\)\*\+,;=:@\xA0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|[\uD800-\uD83E\uD840-\uD87E\uD880-\uD8BE\uD8C0-\uD8FE\uD900-\uD93E\uD940-\uD97E\uD980-\uD9BE\uD9C0-\uD9FE\uDA00-\uDA3E\uDA40-\uDA7E\uDA80-\uDABE\uDAC0-\uDAFE\uDB00-\uDB3E\uDB44-\uDB7E][\uDC00-\uDFFF]|[\uD83F\uD87F\uD8BF\uD8FF\uD93F\uD97F\uD9BF\uD9FF\uDA3F\uDA7F\uDABF\uDAFF\uDB3F\uDB7F][\uDC00-\uDFFD]))*)*)?|(?:(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~!\$&'\(\)\*\+,;=:@\xA0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|[\uD800-\uD83E\uD840-\uD87E\uD880-\uD8BE\uD8C0-\uD8FE\uD900-\uD93E\uD940-\uD97E\uD980-\uD9BE\uD9C0-\uD9FE\uDA00-\uDA3E\uDA40-\uDA7E\uDA80-\uDABE\uDAC0-\uDAFE\uDB00-\uDB3E\uDB44-\uDB7E][\uDC00-\uDFFF]|[\uD83F\uD87F\uD8BF\uD8FF\uD93F\uD97F\uD9BF\uD9FF\uDA3F\uDA7F\uDABF\uDAFF\uDB3F\uDB7F][\uDC00-\uDFFD]))+)(?:\/(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~!\$&'\(\)\*\+,;=:@\xA0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|[\uD800-\uD83E\uD840-\uD87E\uD880-\uD8BE\uD8C0-\uD8FE\uD900-\uD93E\uD940-\uD97E\uD980-\uD9BE\uD9C0-\uD9FE\uDA00-\uDA3E\uDA40-\uDA7E\uDA80-\uDABE\uDAC0-\uDAFE\uDB00-\uDB3E\uDB44-\uDB7E][\uDC00-\uDFFF]|[\uD83F\uD87F\uD8BF\uD8FF\uD93F\uD97F\uD9BF\uD9FF\uDA3F\uDA7F\uDABF\uDAFF\uDB3F\uDB7F][\uDC00-\uDFFD]))*)*|(?!(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~!\$&'\(\)\*\+,;=:@\xA0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|[\uD800-\uD83E\uD840-\uD87E\uD880-\uD8BE\uD8C0-\uD8FE\uD900-\uD93E\uD940-\uD97E\uD980-\uD9BE\uD9C0-\uD9FE\uDA00-\uDA3E\uDA40-\uDA7E\uDA80-\uDABE\uDAC0-\uDAFE\uDB00-\uDB3E\uDB44-\uDB7E][\uDC00-\uDFFF]|[\uD83F\uD87F\uD8BF\uD8FF\uD93F\uD97F\uD9BF\uD9FF\uDA3F\uDA7F\uDABF\uDAFF\uDB3F\uDB7F][\uDC00-\uDFFD])))(?:\?(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~!\$&'\(\)\*\+,;=:@\/\?\xA0-\uD7FF\uE000-\uFDCF\uFDF0-\uFFEF]|[\uD800-\uD83E\uD840-\uD87E\uD880-\uD8BE\uD8C0-\uD8FE\uD900-\uD93E\uD940-\uD97E\uD980-\uD9BE\uD9C0-\uD9FE\uDA00-\uDA3E\uDA40-\uDA7E\uDA80-\uDABE\uDAC0-\uDAFE\uDB00-\uDB3E\uDB44-\uDB7E\uDB80-\uDBBE\uDBC0-\uDBFE][\uDC00-\uDFFF]|[\uD83F\uD87F\uD8BF\uD8FF\uD93F\uD97F\uD9BF\uD9FF\uDA3F\uDA7F\uDABF\uDAFF\uDB3F\uDB7F\uDBBF\uDBFF][\uDC00-\uDFFD])*)?(?:\#(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~!\$&'\(\)\*\+,;=:@\/\?\xA0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]|[\uD800-\uD83E\uD840-\uD87E\uD880-\uD8BE\uD8C0-\uD8FE\uD900-\uD93E\uD940-\uD97E\uD980-\uD9BE\uD9C0-\uD9FE\uDA00-\uDA3E\uDA40-\uDA7E\uDA80-\uDABE\uDAC0-\uDAFE\uDB00-\uDB3E\uDB44-\uDB7E][\uDC00-\uDFFF]|[\uD83F\uD87F\uD8BF\uD8FF\uD93F\uD97F\uD9BF\uD9FF\uDA3F\uDA7F\uDABF\uDAFF\uDB3F\uDB7F][\uDC00-\uDFFD])*)?$
/
i
Open regex in editor

Description

This is a JavaScript port of the URL regex from http://stackoverflow.com/a/190405/384062 that includes a bug fix and some optimization.

Mathias Bynens's Regenerate was used to convert unicode escapes.

Bug fix: Eliminated stray | falsely allowing querystring to contain |

Optimization: Merged alternated character classes in querystring and fragment identifier portions for better performance.

Submitted by Hans Meyer - 9 years ago