Regexp Syntax Summary
Lookahead and Lookbehind Tutorial—Tips &Tricks
Exploring the Linguistics Behind Regular Expressions


Regular Expression Matching Can Be Simple And Fast
ECMAScript regular expressions are getting better! · Mathias Bynens
ES2018: RegExp named capture groups
ES2018: RegExp Unicode property escapes
ES2018: RegExp lookbehind assertions
ES2018: `s` (`dotAll`) flag for regular expressions


free-programming-books/free-programming-books.md at master · EbookFoundation/free-programming-books
hosseinmousavi/Regex.Persian.Language: Collection of Regex for validating, filtering, sanitizing and finding Persian strings
Ftfy – fix Unicode that's broken in various ways | Hacker News
[^ -~]
chalk/ansi-regex: Regular expression for matching ANSI escape codes


Python – Regular Expressions Practical Guide – Developers Area
Python – Regular Expressions Practical Guide – Developers Area
Comparison of regular expression engines - Wikipedia
An introduction to regular expressions - O'Reilly Media
Dr. Regex: Match Nested Brackets with Regex: A new approach
GitHub - mndrix/regex: Regular expressions for Prolog
Regex was taking 5 days to run. So I built a tool that did it in 15 minutes.
Build a Regex Engine in Less than 40 Lines of Code › Nick Drane
Regular Expressions for Data Scientists


Introduction to Regular Expressions in Python
Structural Regular Expressions


AWS WAF Now Supports Regular Expressions (Regex)
code golf - Regex that only matches itself - Programming Puzzles & Code Golf Stack Exchange
sindresorhus/matcher: Simple wildcard matching
sindresorhus/globby: User-friendly glob matching
eriknyquist/librxvm: non-backtracking NFA-based regular expression library, for C and Python


opennota/re2dfa: Transform regular expressions into finite state machines and output Go source code
dveselov/python-pire: Python interface to PIRE


Regular Expressions and Grouping Sets
V8 JavaScript Engine: Upcoming RegExp Features
Language Tags: Addison Phillips Java regexp for language tags


GitHub - zeeshanu/learn-regex: Learn regex the easy way
Regular Expressions Primer and Resource - Advanced Text Searching
GitHub - iogf/crocs: Write regex using pure python class/function syntax and test it better. (Regex for humans).
MIT Mystery Hunt Puzzle Index: Puzzle Data
BBC Radio 4 - Today - Puzzle for Today
Replacing a Complex Regular Expression with a Simple Parser
FuzzyFinder - in 10 lines of Python - Brain Spill


re — Regular Expressions — PyMOTW 3
OWASP Validation Regex Repository - OWASP
Regex Set Scanning with Hyperscan and RE2::Set | 01.org
Java 101: Regular expressions in Java, Part 1 | JavaWorld
Reparse — Reparse 3.0 documentation
I Knew How To Validate An Email Address Until I Read The RFC | You’ve Been Haacked
wregex - How Regular Expression Engines Work


Update: re_search.py Version 0.0.7 | Didier Stevens
The New ‘Absent Operator’ in Ruby’s Regular Expressions – Ruby Inside – Medium
Converting glob patterns to efficient regexes in Perl and JavaScript | mauke [blogs.perl.org]


Java Standard Library — Scala Native 0.1 documentation
research!rsc: Glob Matching Can Be Simple And Fast Too
Beyond Regular Expressions - Lex and Yacc
Fuzzing is magic - Or how I found a panic in Rust's regex library
A comparison of regex engines – Rust Leipzig


#12818 (regex: badly needs fuzzing) – Boost C++ Libraries


V8 JavaScript Engine: Speeding up V8 Regular Expressions
Let’s Stop Ascribing Meaning to Code Points | Hacker News
GitHub - laurikari/tre: The approximate regex matching library and agrep command line tool.


RegEx Face Off
lk-geimfari/expynent: A library that provides regex patterns. If you hate to write regular expressions, then expynent can help you.
RunKit + npm: regexgen
Yesterdays Regex — Geek&Poke
Regular Expressions for Google Analytics - Regular-Expressions-Google-Analytics.pdf
Runaway Regular Expressions: Catastrophic Backtracking
ripgrep code review
Adventures in the land of substrings and RegExps.


Regex Hub - Useful Regex Patterns
RegexOne - Learn Regular Expressions - Lesson 1: An Introduction, and the ABCs
Visualizing Regular Expressions: regexper.com – Medium
Regex 101 | Hacker News
Big Performance Improvement for std.regex – The D Blog
Regex that only matches itself - Programming Puzzles & Code Golf Stack Exchange


Unicode property escapes in JavaScript regular expressions · Mathias Bynens
jamiejennings/rosie-pattern-language: Rosie Pattern Language (RPL) and the Rosie Pattern Engine
Recursive Regular Expression


rust-lang-nursery/regex: An implementation of regular expressions for Rust. This implementation uses finite automata and guarantees linear time matching on all inputs.
ripgrep is faster than {grep, ag, git grep, ucg, pt, sift} - Andrew Gallant's Blog
Demystifying The Regular Expression That Checks If A Number Is Prime – G'd Up Code
The 100% correct way to validate email addresses


SRL - Simple Regex Language
Google Code Archive - Long-term storage for Google Code Project Hosting.
why GNU grep is fast
s4ke/moar: Deterministic Regular Expressions with Backreferences
Maniagnosis - A deep dive into regular expression derivatives for lexical analysis
Ann: Typed regular expressions | Drup's thingies
Regular expression to match line that doesn't contain a word? - Stack Overflow
Validating Email Addresses with a Regex? Do yourself a favor and don’t – /dev/random
Apocalypse 5: Pattern Matching
kkos/oniguruma: regular expression library
Boost.Regex 5.1.1 - 1.61.0
A Regular Expression Matcher (2007) | Hacker News


moovweb/rubex: Super Fast Regex in Go
Stack Overflow Outage Postmortem | Hacker News
Stack Exchange Network Status — Outage Postmortem - July 20, 2016


Fast, Elegant Regexes in Haskell
Making sense of regular expressions


Eigenstate :: Implementing A Simple Regex Debugger
languagengine - Blog - Regex Edit Distance
Regular expressions you can read: A new visual syntax (and UI) — Medium
BurntSushi/rure-go: Go bindings to Rust's regex engine.


Debuggex: Online visual regex tester. JavaScript, Python, and PCRE.
regex - How to make perl regexes matches ASCII and Unicode - Stack Overflow
EReg - Haxe API
Practice Makes Regexp - New regexp book from Reuven Lerner
Elliot Chance - It's Impossible to Validate an Email Address
Best Practices for Regular Expressions - Codacy | Blog


mathiasbynens/regex-trie-cli - Create regular expression patterns based on a list of strings to be matched
Puzzle | LinkedIn Engineering
Hard code golf: Regex for divisibility by 7 - Programming Puzzles & Code Golf Stack Exchange
V8 JavaScript Engine: RegExp lookbehind assertions


Understanding the basics of Regular Expression
[no title]
kirbyfan64/rejit: A work-in-progress JIT-powered regex engine
CaptainCrowbar/unicorn-lib: Unicode library for C++
String Parsing in SQL
GitHub - akoumjian/datefinder: Find dates inside text using Python and get back datetime objects


How I fixed Atom - davidvgalbraith
alexflint/go-restructure: Match regular expressions into struct fields
regex cheat sheet at DuckDuckGo
Javarevisited: 10 examples of grep command in UNIX and Linux
d10/regjsgen · GitHub
jviereck/regjsparser · GitHub
mathiasbynens/regenerate · GitHub
mathiasbynens/regexpu-core · GitHub


Regex Crossword
Gregable: Regular Expression Crossword Puzzle
Email address validation and encodings
Shell scripting notes – searching matching filenames and matching content | Kev's Development Toolbox
Regular Expression Basics | BoTree Technologies
RegExp class - dart:core library - Dart API


Python's Hidden Regular Expression Gems | Armin Ronacher's Thoughts and Writings
Abandon - Validate Facebook URLs & Twitter Usernames with PHP Regular Expression


Siderite's Blog: Super Fast and Accurate string distance algorithm: Sift4
the-emacs-problem - steveyegge2
How We Match Regular Expressions | 01.org
LightboxTech/liblightgrep · GitHub
Hyperscan | 01.org
Exact String Matching Algorithms | HackerEarth
Introduction to regular expressions
Working with Email Addresses in SQL - Mode Blog


The Best Regex Trick
Fast String Matching | JW Player
Perl Regular Expression Matching is NP-Hard
Converting regular expressions into nondeterministic finite automata (NFAs): An implementation in Java
Pattern-matching regular expressions in Scheme using derivatives
yandex/pire · GitHub
Perl Incompatible Regular Expressions library
A regular expression converter - hokein/Automata.js · GitHub


fent/randexp.js @ GitHub
Create random strings that match a given regular expression.
Snobol Pattern Matching in Python
Character Model for the World Wide Web: String Matching and Searching
PCRE - Perl Compatible Regular Expressions
Syntax extensions and regular expressions for Rust - Andrew Gallant's Blog
regex - Regular expression for unicode in java 7 - Stack Overflow


New regular expression features in ECMAScript 6
Using wildcard matching in any programming language | RLV Blog
Dennis Yurichev: 23-Jul-2015: Fuzzy string matching + simplest possible spellchecking + hunting for typos and misspellings in Wikipedia.
Automatic Generation of Text Extraction Patterns from Examples
swift - NSRegularExpression regex replace Greek Unicode text - Stack Overflow
This Week in D: June 28, 2015
Ragel State Machine Compiler | Colm Networks
Five Invaluable Techniques to Improve Regex Performance : programming
Five Invaluable Techniques to Improve Regex Performance


RohitK89/LogScraper · GitHub
Xeger - More expressive regular expressions for JavaScript. Pronounced "zeeger"
Regexes: The Bad, the Better, and the Best : programming
Regexes: the Bad, the Better, and the Best
Alternatives To Regular Expressions
jonathantneal/regexp-escape · GitHub
Implementing Regular Expressions


Emojineering Part 2: Implementing Hashtag Emoji - Instagram Engineering
PatternMatcher | Android Developers


Python regex tokenization of Unicode string not working as expected - Stack Overflow
Unicode and Boost.Regex - 1.58.0
In search of the perfect URL validation regex
Is there a regular expression to detect a valid regular expression? - Stack Overflow


google/re2j · GitHub
neuront/python-reloon · GitHub
is.js - micro check library
Wrestling PCRE
Understanding Regular Expressions 2: Groups and Captures


Email Regex that works 99.99% | Hacker News
Email Regex - Everything About Email Regular Expression!
RegExp.prototype.unicode - JavaScript | MDN
Regular Expressions in T-SQL - SQLTeam.com
Regular Expressions in T-SQL - Ken Henderson's WebLog - Site Home - MSDN Blogs
SQL Server: Regular Expressions for Efficient SQL Querying


mathiasbynens/regexpu · GitHub
A source code transpiler that enables the use of ES6 Unicode regular expressions in ES5.
Unicode Regular Expression Engines // Speaker Deck
A JIT for grepping: jrep and rejit [LWN.net]
“grep was a private command of mine for quite a while before i made it public.” -Ken Thompson — Medium
Liniarc/regexProgram · GitHub


Automatic Generation of Text Extraction Patterns from Examples
'regex' tag wiki - Stack Overflow
Regular expression cheat sheet
cheatsheet - regex-cheatsheet.pdf
Regular Expression Cheat Sheet
[.NET Core] System.Text.RegularExpressions Source Code : programming


regex - Unicode expression failing in preg_match after php and apache update - Stack Overflow


Maybe regexp is the wrong tool for this job. I'm just saying. : programming
Full email validation regex (RFC 2822) | Hacker News
Mathias Bynens on Twitter: "Support for the ES6 `y` flag for sticky regular expressions just landed in V8: https://t.co/XVx6JMlLwT Coming soon to Chrome, Opera & Node!"
sunlightlabs/jellyfish · GitHub
a python library for doing approximate and phonetic matching of strings.


Unicode-aware regular expressions in ES6 · Mathias Bynens
What you should know about JavaScript regular expressions


sindresorhus/mapcode-regex · GitHub
Regular expression for matching mapcodes
charles leifer | Playing with Python Magic Methods to make a nicer Regex API
regex /(?x: (w+) s (w+) )/ hacker news at DuckDuckGo
Understanding and Using Regular Expressions


In search of the perfect URL validation regex
TCL Regular Expression Examples
hrothgar/lexitron · GitHub
regex on a english dictionary
TRE — The free and portable approximate regex matching library.
Comparison of regular expression engines - Wikipedia, the free encyclopedia
List of regular expression software - Wikipedia, the free encyclopedia
regex 2014.05.23 : Python Package Index


Andrew Gallant's Blog :: Syntax extensions and regular expressions for Rust
Regular Expressions without Fear - The Changelog
VerbalExpressions ♥ Open Source


How to correctly detect credit card type
gskinner.com: gBlog: RegExr v2: Build, Test, & Learn RegEx
Regex Tutorial—From Regex 101 to Advanced Regex
Rx - a backend for writing regex debuggers for Perl
Learn regular expressions in about 55 minutes - Sam Hughes
Mastering Python Regular Expressions by Félix López and Víctor Romero


Try Regex—an interactive regex tutorial
The regex that broke a server | Vlad Mihalcea's Blog
xkcd 1313: Regex Golf (Part 2: Infinite Problems)
The Regexinator: a Google Analytics Regex Filter Compiler - LunaMetrics
Solving a Regular Expression Crossword with Haskell, Part 1
Regular Expressions in ANS Forth


The Developer’s RegEx Survival Guide: 15 Rules for Making Sense of Regular Expressions
Windows with C++ - Using Regular Expressions with Modern C++
command center: Regular expressions in lexing and parsing
HTML5 Input Patterns and Invalid Regex
Regex Golf, xkcd, and Peter Norvig - Slashdot
xkcd: Regex Golf
Solution to xkcd 1313
thebinarysearchtree/regexpbuilderjs · GitHub
igrigorik/textquery · GitHub


Regex Golf - discussion on Hacker News
Regex Golf - discussion on Reddit
Regex Golf
Hexpress by krainboltgreene
andrewberls/regularity · GitHub
CommonRegex - A collection of common regular expressions bundled with an easy to use interface.


Rex @ rise4fun from Microsoft
../re/testregex.mm mm document
man/man1/testregex.html man page
The best online regular expression / RegEx testers and builder-tools as of 2013 | Technical Programming and Design
SLRE: Super Light Regular Expression library


Of running multiple regexp at once
JSON parser as a single Perl Regex
Parsing JSON with a single regex | brian d foy [blogs.perl.org]
Matt Swanson - How not to validate email addresses


Meet RegExpBuilder: Verbal Expressions' rich, older cousin - The Changelog
Official IETF regex for URLs
RFC 3986 - Uniform Resource Identifier (URI): Generic Syntax
thebinarysearchtree/RegExpBuilder - GitHub


A Recursive Regular Expression for Matching Regular Expressions - Abrazolica
Bitsets match regular expressions, compactly - Paul Khuong mostly on Lisp
12 Resources For Mastering Regular Expressions
Using Python's AST parser to create regular expressions from English
noprompt/frak · GitHub
Transform collections of strings into regular expressions
Build Regex - A Simple RegEx GUI


jehna/VerbalExpressions · GitHub
Just released a major update for my site. What do you guys think? | Hacker News
Love Rubular? Here are a few open source copycats to checkout. - The Changelog
Regex Crossword
046 Regex on Vimeo
Parsley: A Pattern-Matching Language Based on OMeta and Python - github


Finite State Machines and Regular Expressions - General Programming - Articles - Articles - GameDev.net
GROK regex test page
Standard GROK regex patterns


Learn Regular Expressions - Pony Foo
The true power of regular expressions
Counting with Regular Expressions - Abrazolica
Stop Validating Email Addresses With Your Complex Regex - davidcel.is
JavaScript Regular Expression Enlightenment - Tech.Pro
Stop Avoiding Regular Expressions Damn It - bradt.ca


Brain Dump (english): Arithmetic with Regexps
Why the hell am I building a product with a tiny market? - Debuggex
Best of Fluent 2012: /Reg(exp){2}lained/: Demystifying Regular Expressions - YouTube
An example driven guide to regular expressions | JoeJag :: Tech
Python, Catastrophic Regular Expressions and the GIL


Nested Regular Expressions explained | Linguistic forms
Details of Regular Expression Behavior
Bastards Book of Regular Expressions by Dan Nguyen [PDF/iPad/Kindle]
HTML5 Pattern
regexs for HTML5 input validation
REBEL - Kendall Frey's Website
Regular Expression Based Esoteric Language - a declarative programming language that works by iteratively replacing substrings
petere/pgpcre · GitHub


java - Cancelling a long running regex match? - Stack Overflow
Comparison of regular expression engines - Wikipedia, the free encyclopedia
Parsing Techniques - A Practical Guide | Hacker News
print "Me" -- portable perspectives
k-takata/Onigmo · GitHub
Ruby 2.0
Debuggex: A visual regular expression debugger
Can You Do the Regular Expression Crossword? - Slashdot
Security Briefs - Regular Expression Denial of Service Attacks and Defenses
Collaborative Manuscript Transcription: Bending Regular Expressions to Express Uncertainty
Regex Challenge - Week Twenty
chess move notation using the algebraic notation
A regular expression crossword puzzle [pdf]
Regex Challenge - Week Nineteen
all the valid HTML tag names in as few characters as possible


RegexOne - Learn regular expressions with interactive examples
Regular expressions - Rosetta Code
The 30 Minute Regex Tutorial - CodeProject
I don't like Regex... - CodeProject
Regex Challenge - Week Eighteen
check if a string is a valid IRC message sent to a user or channel
harthur/replace · GitHub
Command line search and replace utility (with js regex)
AT&T Research regex(3) regression tests
logentries/re2-java · GitHub
Vim Regular Expressions 101
Printable Regular Expressions Cheatsheet
Validate an E-Mail Address with PHP, the Right Way | Linux Journal
Regex Challenge - Week Seventeen
match valid regular expressions - just literal characters, character classes, and a few other minor features
Microsoft Research Mobile - The GRETA Regular Expression Template Archive
Boost C++ - References and Further Information - 1.52.0
tweetregs/regexes.md at master · pkedrosky/tweetregs · GitHub
Advanced Filters: Excel's Amazing Alternative To Regex
regex-dna benchmark | Computer Language Benchmarks Game
Home · gabriel-weaver/xutools Wiki · GitHub
ArsalanBashir/RegexLove · GitHub


Incremental Regular Expressions
Google Spreadsheet Regular Expression Functions Are Insanely Useful
10 Java Regular Expression Examples You Should Know
Regex Challenge - Week Sixteen
match the elements with chemical numbers of above 50
Regex Challenge - Week Fifteen
match musical chord names such as Cmin, Bmaj
Regex Challenge - Week Fourteen
match all the valid chemical element short names
BlackOdd: Learning Regular Expressions / Regex [Part 1] - Character Classes, Elements and Quantifiers
Here's what ICT should really teach kids: how to do regular expressions | Technology | guardian.co.uk


How to Find or Validate an Email Address
Regex Challenge - Week Thirteen
match strings which have a word repeated directly below the same word on the previous line
Regex Challenge - Week Eleven
one space between words, and two spaces after full stops
Regex Challenge - Week Eleven
match strings where the letters are in alphabetical order
Regex Challenge - Week Ten
turn a sentence into a number of "tokens" that would be suitable for something like a search engine to use as keywords
Regex Challenge - Week Nine
parse MarkDown links
Regex Challenge - Week Eight
match (immediately) repeating MarkDown list items
eriksank/alt-regex-engine · GitHub States of the type attribute — HTML5
My favorite regex of all time - good coders code, great reuse
It matches all ASCII characters from the space to the tilde


Regular Expressions Will Stab You in the Back - Cue:tech
Rubular - a Ruby regular expression editor | Hacker News
A Common Gotcha When Using Ruby Regexps For Input Validation - Jerod Santo
ReDoS - Wikipedia, the free encyclopedia
Validating a US Social Security Number with ColdFusion and Regex | Interactive.Octopus
REL by Imaginatio
Regex Challenge - Week Seven
match valid domain names with protocols (http and https) in front of them and an optional slash (/) behind them
Regex Challenge - Week Six
match IPv4 addresses in the syntaxes (dotted decimal, dotted hexadecimal, dotted octal, hexadecimal, decimal and octal) specified on Wikipedia
Proton - A Declarative Multitouch Framework
Regex Challenge - Week Five
match correctly formatted numbers
Regex Challenge - Week Four
turn italic MarkDown into HTML italic


xkcd #208: Regular Expressions
Regular Expressions Illustrated (prototype)
Regex Challenge - Week Three
match dates in YYYY/MM/DD HH:MM(:SS) format
Cryptic Ruby Global Variables and Their Meanings
natefaubion/matches.js · GitHub
Regex Challenge - Week Two
match a grayscale CSS colour
Regex Tuesday Challenge #1 (xpost from /r/javascript) : programming
Regex Challenge - Week One
make a regex which finds and highlights repeated words in a body of text
Stop Validating Email Addresses With Regex : programming
Stop validating email addresses with your complex regex | Hacker News
Stop Validating Email Addresses With Your Complex Regex - davidcelis.com


The Binary Search Tree: RegExpBuilder


UTS #18: Unicode Regular Expressions
UTS #18, Unicode Regular Expressions, Version 15 Released from announcements_at_unicode.org on 2012-07-19 (Unicode Mail List Archive)
syntax across languages per category
Patterns for variable names in different programming languages
Comparing E-mail Address Validating Regular Expressions
C++11 regex cheatsheet | C++ Rocks
Codular - An Introduction to Regular Expressions
Regex Engine
Compare Regular Expression Flavors
Parsing regular expressions with recursive descent | Hacker News
Parsing regular expressions with recursive descent


Boost.Regex - Boost 1.50.0
Perl Regular Expression Syntax - Boost 1.47.0
The Odds & Ends of Python Regular Expressions | Python Central - Python Programming Examples, Tutorials
ReFiddle: Fiddle for Regexp testing | Hacker News
The true power of regular expressions
Structural Regular Expressions - Rob Pike
Compute the intersection of two regular expressions in Python 3 @ Things Of Interest
Last week I learnt regex behaves differently depending on what your locale is set to. My colleague who came across this has been programming for 30 years and had never come across this before. Wanted to share. Link is the best site I can find to explain i
Locale specific behavior in the regex library? - Stack Overflow
Regex.Timeout in the .NET 4.5 Base Class Library


regex - Perl Compatible Regular Expression (PCRE) in Python - Stack Overflow
Chromium Blog: Irregexp, Google Chrome's New Regexp Implementation
Mac App Store - iRegEx
37 Tested PHP, Perl, and JavaScript Regular Expressions
Using Regular Expressions in Visual Studio


Best online regex testers Regular expression testers online free
On Structural Regexes – lubutu

Number of links: 400

Also see links to other regex testing websites/programs on the Similiar Tools page.