Js Regex — Free Javascript Tutorial
Learn Js Regex in Javascript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.
TL;DR: Learn Js Regex in Javascript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.
Written & reviewed by the Syllab.in Academic Team (CBSE/NCERT subject experts) · Updated
Js Regex in Javascript
Regular Expressions (regex) are patterns used to match, search, and manipulate text. In JavaScript, regex literals are written between forward slashes: /pattern/flags.
Core syntax: . (any character), * (0 or more), + (1 or more), ? (0 or 1), ^ (start), $ (end), [abc] (character class), [^abc] (not), \d (digit), \w (word char), \s (whitespace), {n,m} (repeat n to m times).
Flags: g (global — find all matches), i (case-insensitive), m (multiline). Methods: test() (returns boolean), match() (returns array), replace() (substitute), split() (divide by pattern), exec() (iterative matching).
Common use cases: form validation (email, phone, password), data extraction (find all URLs in text), text formatting (add spaces to phone numbers), sanitisation (remove HTML tags).
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