This is a new technology, part of the ECMAScript 2015 (ES6) standard .
This technology's specification has been finalized, but check the compatibility table for usage and implementation status in various browsers.

The Math.fround() function returns the nearest single precision float representation of a number.




A number.


Because fround() is a static method of Math, you always use it as Math.fround(), rather than as a method of a Math object you created (Math is not a constructor).


Using Math.fround()

Math.fround(0);     // 0
Math.fround(1);     // 1
Math.fround(1.337); // 1.3370000123977661
Math.fround(1.5);   // 1.5
Math.fround(NaN);   // NaN


This can be emulated with the following function, if Float32Array are supported:

Math.fround = Math.fround || function(x) {
  return new Float32Array([x])[0];


Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Math.fround' in that specification.
Standard Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 38 26 (26) Not supported 25 7.1
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support Not supported ? (Yes) Not supported Not supported 8

See also

Document Tags and Contributors

Contributors to this page: fscholz, xfq, Mingun, ziyunfei, realityking
Last updated by: fscholz,