Exponentiation assignment (**=)

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since March 2017.

The **= operator performs exponentiation on the two operands and assigns the result to the left operand.

Try it

x **= y

x **= y is equivalent to x = x ** y, except that the expression x is only evaluated once.

let bar = 5;
bar **= 2; // 25

Other non-BigInt values are coerced to numbers:

let baz = 5;
baz **= "foo"; // NaN

let foo = 3n;
foo **= 2n; // 9n
foo **= 1; // TypeError: Cannot mix BigInt and other types, use explicit conversions

Specification
ECMAScript Language Specification # sec-assignment-operators

	Desktop					Mobile						Server
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	Deno	Node.js
`Exponentiation_assignment`	52	14	52	39	10.1	52	52	41	10.3	6.0	51	1.0	7.0.0