Number.EPSILON

The Number.EPSILON property represents the difference between 1 and the smallest floating point number greater than 1.

You do not have to create a Number object to access this static property (use Number.EPSILON).

Property attributes of Number.EPSILON
Writable no
Enumerable no
Configurable no

Description

The EPSILON property has a value of approximately 2.2204460492503130808472633361816E-16, or 2^-52.

Examples

Testing equality

x = 0.2;
y = 0.3;
z = 0.1;
equal = (Math.abs(x - y + z) < Number.EPSILON);

Polyfill

if (Number.EPSILON === undefined) {
    Number.EPSILON = Math.pow(2, -52);
}

Specifications

Specification
ECMAScript Language Specification (ECMAScript)
# sec-number.epsilon

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
EPSILON
34
12
25
No
21
9
≤37
34
25
21
9
2.0

See also

  • A polyfill of Number.EPSILON is available in core-js
  • The Number object it belongs to

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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/EPSILON