RegExp.prototype.multiline
BaselineWidely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
Themultiline accessor property ofRegExp instances returns whether or not them flag is used with this regular expression.
Try it
const regex1 = /^football/;const regex2 = /^football/m;console.log(regex1.multiline);// Expected output: falseconsole.log(regex2.multiline);// Expected output: trueconsole.log(regex1.test("rugby\nfootball"));// Expected output: falseconsole.log(regex2.test("rugby\nfootball"));// Expected output: trueDescription
RegExp.prototype.multiline has the valuetrue if them flag was used; otherwise,false. Them flag indicates that a multiline input string should be treated as multiple lines. For example, ifm is used,^ and$ change from matching at only the start or end of the entire string to the start or end of any line within the string.
The set accessor ofmultiline isundefined. You cannot change this property directly.
Examples
Using multiline
js
const regex = /^foo/m;console.log(regex.multiline); // trueSpecifications
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-get-regexp.prototype.multiline |