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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

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
EPSILON 34 12 25 No 21 9
Mobile
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
EPSILON ≤37 34 25 21 9 2.0
Server
Node.js
EPSILON 0.12

See also

  • The Number object it belongs to

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