regex101: build, test, and debug regex | Regular Expressions 101
https://regex101.com/
Regular expression tester with syntax highlighting, explanation, cheat sheet for PHP/PCRE, Python, GO, JavaScript, Java. Features a regex quiz & library.
RegExr: Learn, Build, & Test RegEx | Expression
https://regexr.com/
Regular expression tester with syntax highlighting, PHP / PCRE & JS Support, contextual help, cheat sheet, reference, and searchable community patterns.
Regular expression - Wikipedia
https://en.wikipedia.org/wiki/Regular_expression
A regular expression (shortened as regex or regexp; also referred to as rational expression) is a sequence of characters that define a search pattern.
Шпаргалка по регулярным выражениям
http://website-lab.ru/article/regexp/shpargalka_po_regulyarnyim_vyirajeniyam/
Регулярные выражения. JavaScript. RegExp.
Регулярные выражения за 15 минут | Антон Прибора
https://anton-pribora.ru/articles/it/regular-expressions/
https://developer.mozilla.org/ru/docs/Web/JavaScript/Reference/Global_Objects/RegExp - регулярные выражения JavaScript.
Regular Expression Language - Quick Reference | Microsoft Docs
https://docs.microsoft.com/en-us/dotnet/standard/base-types/regular-expression-language-quick-reference
In this quick reference, learn to use regular expression patterns to match input text. A pattern has one or more character literals, operators, or constructs.
Regular Expressions Quick Start
https://www.regular-expressions.info/quickstart.html
This quick start gets you up to speed quickly with regular expressions. Obviously, this brief introduction cannot explain everything there is to know about regular expressions. For detailed...
JavaScript RegExp Reference
https://www.w3schools.com/jsref/jsref_obj_regexp.asp
Regular expressions are used to perform pattern-matching and "search-and-replace" functions on text. For a tutorial about Regular Expressions, read our JavaScript RegExp Tutorial.
Не бойтесь регулярных выражений. Regex за 20 минут! - YouTube
https://www.youtube.com/watch?v=_pLpx6btq6U
Основы / Regular Expressions / RegEx / RegExp.
Methods of RegExp and String
https://javascript.info/regexp-methods
If the regexp doesn't have flag g, then it returns the first match as an array with capturing groups and properties index (position of the match), input (input string, equals str)
Regex Tester and Debugger Online - Javascript, PCRE, PHP
https://www.regextester.com/
Regular Expression Tester with highlighting for Javascript and PCRE. Quickly test and debug your regex. Results update in real-time as you type. Roll over a match or expression for details.