MeasureThat.net

Run results for: toFixed vs toPrecision vs Math.round() vs Math.floorfast vs MDN round_to_precision

Added MDN round to precision function: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/round

Go to the benchmark
Run details:
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.1 Safari/605.1.15
Safari 13
Mac OS X 10.14.6
Desktop
4 years ago
Test name Executions per second
toFixed(4) 5864440.0 Ops/sec
toPrecision(4).toString() 5077134.5 Ops/sec
(Math.round(*10000)/10000).toString() 4707883.5 Ops/sec
Math.floor fast 12134922.0 Ops/sec
precisition round 2180206.8 Ops/sec
Script Preparation code:
AخA
 
var someFloat = 0.123456789;
 var round_to_precision = function (x, precision) {
    var y = +x + (precision === undefined ? 0.5 : precision/2);
    return y - (y % (precision === undefined ? 1 : +precision));
};
Tests:

  • toFixed(4)

     
    someFloat.toFixed(4);

  • toPrecision(4).toString()

     
    someFloat.toPrecision(4);

  • (Math.round(*10000)/10000).toString()

    ​x
     
    (Math.round(someFloat*10000)/10000);
    ​

  • Math.floor fast

     
    ~~(someFloat * 10000) / 10000;

  • precisition round

     
    round_to_precision(someFloat, 4);