Run results for: Math.sqrt() vs. Binary search sqrt

Run details:

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Mobile Safari/537.36

Browser: Chrome Mobile 135

Operating system: Android

Device Platform: Mobile

Date tested: one year ago

Benchmark engine: Benchmark.js

Math.sqrt()

36.9M/s

Binary search sqrt

1.9M/s

View exact numbers

Test name	Executions per second
✓ Math.sqrt()	36,925,936 Ops/sec
Binary search sqrt	1,889,846 Ops/sec

Script Preparation code:

function sqrt(x) {
  if (x < 0.0)
    return NaN;
  if (x < 1.0)
    return 1.0 / sqrt(1.0 / x);
  let xhi = x;
  let xlo = 0.0;
  let guess = x / 2.0;
  let next;
  while ((guess * guess) != x) {
    if ((guess * guess) > x)
      xhi = guess;
    else xlo = guess;
    if ((next = (xhi + xlo) / 2.0) == guess)
      break;
    guess = next;
  }
  return guess;
}

Tests:

Math.sqrt()
Math.sqrt(Math.random() * 1000000);
Binary search sqrt
sqrt(Math.random() * 1000000);