Subtraction assignment (-=)

The subtraction assignment operator (-=) subtracts the value of the right operand from a variable and assigns the result to the variable.

Syntax

x -= y // x = x - y

Examples

Using subtraction assignment

// Assuming the following variable
//  bar = 5

bar -= 2     // 3
bar -= 'foo' // NaN

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
Subtraction_assignment
1
12
1
3
3
1
1
18
4
10.1
1
1.0

See also

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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction_assignment