Regular Expressions 101

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Community Patterns

18

best youtube id match ( iframe embed replace ready )

Recommended
PCRE (PHP <7.3)
MATCH ANY YOUTUBE ID author : mi-ca v1.0 – 2017.03.08 This Regex match any youtube url and grab the ID. Embed ready √ --...
Submitted by mi-ca.ch - 6 years ago
29

Cron schedule

Recommended
PCRE (PHP <7.3)
Validate cron lines (even the ones commented out)
Submitted by anonymous - 8 years ago
32

Strict Password Validator

ECMAScript (JavaScript)
This regex matches only when all the following are true: password must contain 1 number (0-9) password must contain 1 uppercase letters password must contain 1 lowercase letters password must contain 1 non-alpha numeric number...
Submitted by qho - 7 years ago (Last modified a year ago)
11

CSS Color Matcher

ECMAScript (JavaScript)
Pattern matching and extracting color code formats using RegEx. https://github.com/Kyza/color-regex/
Submitted by Kyza - a year ago
27

Parsing browser User Agents

PCRE (PHP <7.3)
From a (fairly large) list of User Agent strings, extract the OS, Browser, and Device Type.
Submitted by OnlineCop - 10 years ago (Last modified a year ago)
18

Get path from any text

Recommended
PCRE2 (PHP >=7.3)
Get path (windows style) from any type of text (error message, e-mail corps ...), quoted or not. THIS IS THE SINGLE LINE VERSION !_ If you want understand how it work or edit it, go https://regex101.com/r/7o2fyy Relative path are not supported...
Submitted by nitrateag - 2 years ago (Last modified a year ago)
10

Conventional Commits validation

Python
This regex prevents the writing of non-standard conventional commits. I'm available on my github
Submitted by Krisque - 3 years ago (Last modified 3 years ago)
14

RFC3339 DateTime

Recommended
PCRE (PHP <7.3)
Validates a RFC3339 DateTime format. Does not validates the Data
Submitted by anonymous - 9 years ago
9

Fiddler raw body to PHP array

PCRE (PHP <7.3)
no description available
Submitted by garsax - 9 years ago
8

IP Address (with 0s)

ECMAScript (JavaScript)
Matches all valid IP addresses from 0.0.0.0 to 255.255.255.255
Submitted by Ryan Plummer - 9 years ago
11

youtube url match

ECMAScript (JavaScript)
extract video id, index, play list id from youtube url
Submitted by anonymous - 9 years ago
18

Email (RFC2822)

Recommended
ECMAScript (JavaScript)
Email address compliant with RFC2822
Submitted by Jago - 9 years ago
9

extract subdomain(if available) or domain from URL

Python
This regex should extract the subdomain, if any, or the domain, if no subdomain is used, from an arbitrary URL
Submitted by trevi@twanda.com - 9 years ago
11

IPv4 Validator

PCRE (PHP <7.3)
no description available
Submitted by anonymous - 4 years ago (Last modified a year ago)
14

Email regex validation

ECMAScript (JavaScript)
RegEx email /^((?!\.)[\w-_.]*)(@\w+)(\.\w+(\.\w+)?)$/gim; Just playing with Reg Ex. This to validate emails in following ways ...
Submitted by https://www.linkedin.com/in/peralta-steve-atileon/ - 6 years ago (Last modified a year ago)
24

grab valid css rules and properties

ECMAScript (JavaScript)
no description available
Submitted by Pavel Dominguez - 9 years ago
10

Find Reddit Threads

Python
Simply searches for the thread-id in any kind of valid reddit-URL.
Submitted by Mio - 10 years ago
10

entity

Python
no description available
Submitted by anonymous - 9 years ago
82

Distinguish torrent files (series vs movies)

Python
A neat regex for finding out whether a given torrent name is a series or a movie. Returns the full name of the series with the separator needed to make it pretty (ie, replace it with space or what you want). Also returns the season number or the year for the movie/series, depending on what was prev...
Submitted by Firas Dib - 10 years ago (Last modified a year ago)
13

US Currency Format

ECMAScript (JavaScript)
no description available
Submitted by anonymous - 9 years ago
123...900

Community Library Entry

0

Regular Expression
PCRE (PHP <7.3)

/
(?P<Element><(?P<TagName>[:_A-z][-.0-9:_A-z\xB7]*)(?:[\x09\x0A\x0D\x20]+[:_A-z][-.0-9:_A-z\xB7]*[\x09\x0A\x0D\x20]*=[\x09\x0A\x0D\x20]*(?:"(?:[^<&"]|&(?:[:_A-z][-.0-9:_A-z\xB7]*|#(?:[0-9]+|x[0-9a-fA-F]+));)*"|'(?:[^<&']|&(?:[:_A-z][-.0-9:_A-z\xB7]*|#(?:[0-9]+|x[0-9a-fA-F]+));)*'))*[\x09\x0A\x0D\x20]*(?:>(?:(?:[^<&\]]|](?!]>))*(?:(?:(?P>Element)|&(?:[:_A-z][-.0-9:_A-z\xB7]*|#(?:[0-9]+|x[0-9a-fA-F]+));|<!\[CDATA\[(?:[^\x01-\x08\x0B\x0C\x0E-\x1F\x5D]|](?!]>))*]]>|<\?[:_A-z][-.0-9:_A-z\xB7]*(?<!(?i:\?xml))(?:[\x09\x0A\x0D\x20]+(?:[^\x01-\x08\x0B\x0C\x0E-\x1F\x3F]|\?(?!>))*)?\?>|<!--(?:[^\x01-\x08\x0B\x0C\x0E-\x1F\x2D]|-(?!-))*-->)(?:[^<&\]]|](?!]>))*)*)<\/(?P=TagName)[\x09\x0A\x0D\x20]*|\/)>)|&(?:[:_A-z][-.0-9:_A-z\xB7]*|#(?:[0-9]+|x[0-9a-fA-F]+));|<!\[CDATA\[(?:[^\x01-\x08\x0B\x0C\x0E-\x1F\x5D]|](?!]>))*]]>|<\?[:_A-z][-.0-9:_A-z\xB7]*(?<!(?i:\?xml))(?:[\x09\x0A\x0D\x20]+(?:[^\x01-\x08\x0B\x0C\x0E-\x1F\x3F]|\?(?!>))*)?\?>|<!--(?:[^\x01-\x08\x0B\x0C\x0E-\x1F\x2D]|-(?!-))*-->|<!DOCTYPE[\x09\x0A\x0D\x20]+[:_A-z][-.0-9:_A-z\xB7]*(?:[\x09\x0A\x0D\x20]+(?:SYSTEM[\x09\x0A\x0D\x20]+(?:"[^"]*"|'[^']*')|PUBLIC[\x09\x0A\x0D\x20]+(?:"[\x0A\x0D\x20\x21\x23-\x25\x27-\x2F\x3A\x3B\x3D\x3F\x40_0-9A-z]*"|'[\x0A\x0D\x20\x21\x23-\x25\x28-\x2F\x3A\x3B\x3D\x3F\x40_0-9A-z]*')[\x09\x0A\x0D\x20]+(?:"[^"]*"|'[^']*')))?[\x09\x0A\x0D\x20]*(?:\[(?:(?:<!ELEMENT[\x09\x0A\x0D\x20]+[:_A-z][-.0-9:_A-z\xB7]*[\x09\x0A\x0D\x20]+(?:EMPTY|ANY|\([\x09\x0A\x0D\x20]*#PCDATA(?:(?:[\x09\x0A\x0D\x20]*\|[\x09\x0A\x0D\x20]*[:_A-z][-.0-9:_A-z\xB7]*)*[\x09\x0A\x0D\x20]*\)\*|[\x09\x0A\x0D\x20]*\))|(?:(?P<choice>\([\x09\x0A\x0D\x20]*(?:[:_A-z][-.0-9:_A-z\xB7]*|(?P>choice)|(?P>seq))[?*+]?(?:[\x09\x0A\x0D\x20]*\|[\x09\x0A\x0D\x20]*(?:[:_A-z][-.0-9:_A-z\xB7]*|(?P>choice)|(?P>seq))[?*+]?)+[\x09\x0A\x0D\x20]*\))|(?P<seq>\([\x09\x0A\x0D\x20]*(?:[:_A-z][-.0-9:_A-z\xB7]*|(?P>choice)|(?P>seq))[?*+]?(?:[\x09\x0A\x0D\x20]*,[\x09\x0A\x0D\x20]*(?:[:_A-z][-.0-9:_A-z\xB7]*|(?P>choice)|(?P>seq))[?*+]?)*[\x09\x0A\x0D\x20]*\)))[?*+]?)[\x09\x0A\x0D\x20]*>|<!ATTLIST[\x09\x0A\x0D\x20]+[:_A-z][-.0-9:_A-z\xB7]*(?:[\x09\x0A\x0D\x20]+[:_A-z][-.0-9:_A-z\xB7]*[\x09\x0A\x0D\x20]+(?:CDATA|(?:ID(?:REFS?)?|ENTIT(?:Y|IES)|NMTOKENS?)|(?:NOTATION[\x09\x0A\x0D\x20]+\([\x09\x0A\x0D\x20]*[:_A-z][-.0-9:_A-z\xB7]*(?:[\x09\x0A\x0D\x20]*\|[\x09\x0A\x0D\x20]*[:_A-z][-.0-9:_A-z\xB7]*)*[\x09\x0A\x0D\x20]*\)|\([\x09\x0A\x0D\x20]*(?:[-.0-9:_A-z\xB7])+(?:[\x09\x0A\x0D\x20]*\|[\x09\x0A\x0D\x20]*(?:[-.0-9:_A-z\xB7])+)*[\x09\x0A\x0D\x20]*\)))[\x09\x0A\x0D\x20]+(?:#(?:REQUIRED|IMPLIED)|(?:#FIXED[\x09\x0A\x0D\x20]+)?(?:"(?:[^<&"]|&(?:[:_A-z][-.0-9:_A-z\xB7]*|#(?:[0-9]+|x[0-9a-fA-F]+));)*"|'(?:[^<&']|&(?:[:_A-z][-.0-9:_A-z\xB7]*|#(?:[0-9]+|x[0-9a-fA-F]+));)*')))*[\x09\x0A\x0D\x20]*>|(?:<!ENTITY[\x09\x0A\x0D\x20]+[:_A-z][-.0-9:_A-z\xB7]*[\x09\x0A\x0D\x20]+(?:(?:"(?:[^%&"]|%[:_A-z][-.0-9:_A-z\xB7]*;|&(?:[:_A-z][-.0-9:_A-z\xB7]*|#(?:[0-9]+|x[0-9a-fA-F]+));)*"|'(?:[^%&']|%[:_A-z][-.0-9:_A-z\xB7]*;|&(?:[:_A-z][-.0-9:_A-z\xB7]*|#(?:[0-9]+|x[0-9a-fA-F]+));)*')|(?:SYSTEM[\x09\x0A\x0D\x20]+(?:"[^"]*"|'[^']*')|PUBLIC[\x09\x0A\x0D\x20]+(?:"[\x0A\x0D\x20\x21\x23-\x25\x27-\x2F\x3A\x3B\x3D\x3F\x40_0-9A-z]*"|'[\x0A\x0D\x20\x21\x23-\x25\x28-\x2F\x3A\x3B\x3D\x3F\x40_0-9A-z]*')[\x09\x0A\x0D\x20]+(?:"[^"]*"|'[^']*'))(?:[\x09\x0A\x0D\x20]+NDATA[\x09\x0A\x0D\x20]+[:_A-z][-.0-9:_A-z\xB7]*)?)[\x09\x0A\x0D\x20]*>|<!ENTITY[\x09\x0A\x0D\x20]+%[\x09\x0A\x0D\x20]+[:_A-z][-.0-9:_A-z\xB7]*[\x09\x0A\x0D\x20]+(?:(?:"(?:[^%&"]|%[:_A-z][-.0-9:_A-z\xB7]*;|&(?:[:_A-z][-.0-9:_A-z\xB7]*|#(?:[0-9]+|x[0-9a-fA-F]+));)*"|'(?:[^%&']|%[:_A-z][-.0-9:_A-z\xB7]*;|&(?:[:_A-z][-.0-9:_A-z\xB7]*|#(?:[0-9]+|x[0-9a-fA-F]+));)*')|(?:SYSTEM[\x09\x0A\x0D\x20]+(?:"[^"]*"|'[^']*')|PUBLIC[\x09\x0A\x0D\x20]+(?:"[\x0A\x0D\x20\x21\x23-\x25\x27-\x2F\x3A\x3B\x3D\x3F\x40_0-9A-z]*"|'[\x0A\x0D\x20\x21\x23-\x25\x28-\x2F\x3A\x3B\x3D\x3F\x40_0-9A-z]*')[\x09\x0A\x0D\x20]+(?:"[^"]*"|'[^']*')))[\x09\x0A\x0D\x20]*>)|<!NOTATION[\x09\x0A\x0D\x20]+[:_A-z][-.0-9:_A-z\xB7]*[\x09\x0A\x0D\x20]+(?:(?:SYSTEM[\x09\x0A\x0D\x20]+(?:"[^"]*"|'[^']*')|PUBLIC[\x09\x0A\x0D\x20]+(?:"[\x0A\x0D\x20\x21\x23-\x25\x27-\x2F\x3A\x3B\x3D\x3F\x40_0-9A-z]*"|'[\x0A\x0D\x20\x21\x23-\x25\x28-\x2F\x3A\x3B\x3D\x3F\x40_0-9A-z]*')[\x09\x0A\x0D\x20]+(?:"[^"]*"|'[^']*'))|PUBLIC[\x09\x0A\x0D\x20]+(?:"[\x0A\x0D\x20\x21\x23-\x25\x27-\x2F\x3A\x3B\x3D\x3F\x40_0-9A-z]*"|'[\x0A\x0D\x20\x21\x23-\x25\x28-\x2F\x3A\x3B\x3D\x3F\x40_0-9A-z]*'))[\x09\x0A\x0D\x20]*>|<\?[:_A-z][-.0-9:_A-z\xB7]*(?<!(?i:\?xml))(?:[\x09\x0A\x0D\x20]+(?:[^\x01-\x08\x0B\x0C\x0E-\x1F\x3F]|\?(?!>))*)?\?>|<!--(?:[^\x01-\x08\x0B\x0C\x0E-\x1F\x2D]|-(?!-))*-->)|(?:%[:_A-z][-.0-9:_A-z\xB7]*;|[\x09\x0A\x0D\x20]+))*][\x09\x0A\x0D\x20]*)?>
/
gm
Open regex in editor

Description

I created the regexp using the XML-specificaton (https://www.w3.org/TR/xml), but in a simplified format (for example allowing only a narrowed set of tag-name characters). The regular expression is a recursive regexp with backreference. I do not tested extensively the regex with a regex-directed engine, so it is not optimized for that. I used the regexp to check a text-directed regular expression engine developed by me ( Windows-users can test this engine, visit https://www.regex.hu )

Submitted by GyRos - 3 years ago