Contents

• Documentation
• Prototyping and Testing
• Generators
• Learning
• Libraries
• Collections
• Explanation
• Exercises
• Articles
• Books
• Benchmarks

Documentation

• Regular Expression Language - Quick Reference - MSDN documentation about Regex.
• Regular Expressions - MDN chapter about JavaScript regular expressions.
• Perl Regular Expression Syntax - Boost documentation.
• Perl 6 - Regexes in Perl 6.
• PCRE - Concatenated PCRE man pages.
• ECMAScript 6 - New Regexes in ECMAScript 6.
• regex header in C++ - <regex> in C++
• class Pattern in Java - Java 7 docs.
• class Regex in Scala - Scala Regex.
• Python re module - Regular Expressions Python module tutorial.
• Regular Expressions in Perl - Introduction and Reference Links.

Prototyping and Testing

• Debuggex - Online visual Regex tester.
• ExtendsClass - Online visual Regex tester.
• Nodexr - Online node-based Regex editor.
• Regexr - Website for interactive Regex prototyping with syntax highlighting (by @gskinner).
• Regex101 - Online Regex tester, debugger with highlighting.
• Rubular - Ruby-based regular expression editor and tester.
• Rex V - AJAX Regular EXpression eValuator.
• RegViz - Tool for debugging JavaScript regular expressions in a visual way.
• Regulex - JavaScript Regular Expression Visualizer.
• PyRegex - Online Regex tester to check validity of Regex in the Python language Regex subset.
• pythex - Quick way to test your Python regular expressions.
• Regexper - Regex visualizer for JavaScript using railroad diagrams.
• HiFi Regex Tester - Live JavaScript Regular Expression Tester.
• Regex Hero - .NET online Regex tester.
• Regex Storm - .NET Regex tester with highlighting and detailed results output.
• RegEx to Strings - JavaScript library and online tool to generate strings that a regular expression would match.
• RegexPal - JavaScript + PCRE online tester.
• RegexTester - Regular Expression Tester with highlighting for Javascript and PCRE.
• Free Formatter - Free online Regex tester.
• Regex Tester - Golang - A secure regular expression tester. built using Go
• PHP Live Regex - PHP specific regular expression tester with live evaluation and code generation for all PHP's regex functions.

Generators

• Txt2Re - Generate Regular expressions based on a string
• Regex Generator++ - Automatic Generation of Text Extraction Patterns from Examples
• regexgen - Generates regular expressions that match a set of strings.
• RegexGenerator - A tool for generating regular expressions for text extraction (by @MaLeLabTs)
• Gamon's numberic range generator - Regex Numeric Range Generator, when you need to match an integer range.
• rgxg - Command line tool to generate Regex
• Strings to RegEx - JavaScript library and online tool to generate a regular expression that matches strings.
• Regex Guide - Plain Text to Regex Generator.
• grex - A command-line tool and library for generating regular expressions from user-provided test cases.

Learning

• Wikipedia - Entry on regular expressions.
• Learn Regex The Hard Way - In-progress book that quickly teaches you regular expressions.
• Regular Expression Matching Can Be Simple And Fast - Basic concept of how Regex parsing works.
• [PDF] A Tao Of Regular Expressions - What are Regular Expressions.
• Regular-Expressions.info - Informative website for learning regular expressions.
• RexEgg - A regular expressions tutorial that goes deep into advanced features.
• Try Regex - Try Regex is an interactive regular expressions tutorial.
• Udemy - A Basic Introduction To Using Regular Expressions In Programming.
• Codecademy - How to use of regular expression.
• Regex golf - Regex golf with Peter Norvig.
• Python Regular Expressions - A good introduction to Python Regular Expressions from Google.
• /Reg(exp){2}lained/: Demystifying Regular Expressions - Fluent 2012 talk reviewing and visualizing basic and intermediate Regular Expressions.
• Regular Expressions - Everything you should know - PDF Series.
• The Java Tutorials
• Regex Syntax Summary
• How Regexes work
• Learn Regular Expressions for Beginners
• Java Regex Tutorial
• Javascript.info - Regular expressions - Regular expressions section in The Modern JavaScript Tutorial
• Useful Regexes
• Teach Yourself Regular Expressions

Libraries

• Tre - Free and portable approximate Regex matching library.
• Go-Restructure - Match regular expressions into struct fields in Go (by @alexflint). js C#
• js-regex - Chainable API for construting Regexes.
• VerbalExpressions - VerbalExpressions is a cross-language library that helps to construct difficult regular expressions.
• Super Expressive - Super Expressive is a JavaScript library that allows you to build regular expressions in natural language.
• XRegExp - JavaScript Regex library.
• RE2 - RE2 is a fast, safe, thread-friendly alternative to backtracking regular expression engines like those used in PCRE, Perl, and Python. It is a C++ library.
• Hyperscan - High-performance multiple Regex matching library.

Collections

• RegexLib - Regular Expression Library (5000+ indexed expressions).
• Regexhub - Useful Regex Patterns.
• RGXP.RU - Regular Expression Patterns (+testing)

Explanation

• RegexTranslator - A web app to decode Regex into plain English. You can edit it and translate back.
• Explain.pl - Explain Regular Expressions.

Exercises

• HackerRank Regex Challenges - Regex challenges with varying levels of difficulty.
• Redoku - Little Regex Sudoku/Crossword thing (by @padolsey).
• Regex Tuesday - Challenges - Challenge list about Regex.
• Regex Crossword - A crossword puzzle game using regular expressions.
• RegexOne - Learn regular expressions with simple, interactive examples.
• Regex Exercises - Regexp exercises.
• Regular Expression Crossword Puzzle - A crossword puzzle with a neat web interface.

Articles

• 5 Techniques to Improve Regex Performance - Craft your own powerful, yet efficient regex.
• The Bad, the Better, and the Best - How a few characters can make a difference in performance.
• The Greatest Regex Trick Ever - So you're doubtful at the mention of a "best Regex trick"?
• Treat regular expressions as code, not magic - If you don't write them carefully, you can end up with an unmaintainable monstrosity.
• Demystifying The Regular Expression That Checks If A Number Is Prime - How a regular expression can check if a number is prime.
• Regex Tree: a regular expressions processor
• The thirty minute regex tutorial - Regular Expressions in 30 Minutes.
• Regular Expression Matching Can Be Simple And Fast
• Regular Expressions in a post ES6 World
• Regular expression (regex) performance: The fundamental guide
• The New 'Absent Operator' in Ruby's Regular Expressions
• Optimizing regexes in Java
• Use Regex to Test Password Strength in JavaScript
• Java 101 - Regular Expressions in Java.
• Most Crazy Regexes - Stack Overflow
• Regex Humor - Regex jokes and cartoons.
• The true power of regular expressions

Books

• Patterns, Automata, and Regular Expressions - Al Aho and Jeff Ullman (1992) (chapter 10 of Foundations of Computer Science)
• Beginning Regular Expressions - Andrew Watt (2005)
• Mastering Regular Expressions - Jeffrey E.F. Friedl (2006)
• Regular Expression Pocket Reference - Tony Stubblebine (2007)
• Introducing Regular Expressions - Michael Fitzgerald (2012)
• Regular Expressions Cookbook - Jan Goyvaerts & Steven Levithan (2012)
• Mastering Python Regular Expressions - Felix Lopez & Victor Romero (2014)
• JavaScript Regular Expressions - Loiane Groner & Gabriel Manricks (2015)
• Regex - the complete tutorial
• Python re(gex)? - Sundeep Agarwal (2020)

Benchmarks

• Benchmark of Regex Libraries
• Java regular expression library benchmarks – 2015
• Languages Regex Benchmark - It's just a simple Regex benchmark of different programming languages.
• Performance comparison of regular expression engines
• Regex Performance - Performance comparison of regular expression engines.

Cheat Sheets

• Regular Expressions Cheat Sheet
• Regex Cheat Sheet
• MIT Cheat Sheet
• Java Cheat Sheet
• JavaScript Cheat Sheet

Other awesome lists

Other amazingly awesome lists can be found at the official awesome list and here.