So I have this:

new Date().getMilliseconds();

however, on occasion this just yields just 1 or 2 digits, instead of 3.

So I tried using:

new Date().getMilliseconds().toFixed(3);

so that it always is 3 digits, but this seems to always yield 000, and I don't know why. Anyone know how to do this right?

So I have this:

new Date().getMilliseconds();

however, on occasion this just yields just 1 or 2 digits, instead of 3.

So I tried using:

new Date().getMilliseconds().toFixed(3);

so that it always is 3 digits, but this seems to always yield 000, and I don't know why. Anyone know how to do this right?

• javascript
• node.js

3 Answers 3

You can use padStart to pad the string to the desired length:

setInterval(() => {
  const str = String(new Date().getMilliseconds()).padStart(3, '0');
  console.log(str);
}, 99);

This is a somewhat new feature though, so you'll need a polyfill if you want to support older browsers.

toFixed(3) gives you three digits after the decimal point, not before the decimal point, and getMilliseconds() returns an integer value with no significant digits after the decimal point -- so that's why you always get a number ending in .000.

So, as suggested by another poster, you can use padStart. If you didn't want to use that, you could do:

(1000 + new Date().getMilliseconds()).toString().substr(1);

For just the milliseconds, in boring fundamentals:

let m = new Date().getMilliseconds();
if     (m<1){m = "000";}
else if(m<10){m = "00" + m;}
else if(m<100){m = "0" + m;}

Still using fundamentals; now with interactivity and the whole time, with milliseconds.

var myVar = setInterval(myTimer, 100);
function myTimer() {
  let d = new Date();
  let m = d.getMilliseconds();
  
  if(m<1){m = "000" + m;}
  else if(m<10){m = "00" + m;}
  else if(m<100){m = "0" + m;}
  
  var dateString = d.toLocaleTimeString();
  dateString = dateString.replace(" AM", "." + m + " AM");
  dateString = dateString.replace(" PM", "." + m + " PM");
  
  document.getElementById("demo").innerHTML = dateString;
}

<p>Start and stop this clock (always starts at current time with milliseconds):</p>

<p id="demo">Time at some time</p>

<button 
	id="stop" 
    onclick="clearInterval(myVar);
    document.getElementById('restart').style.display='block';
    document.getElementById('stop').style.display='none';" 
    style="display:block;"
>Stop time</button>

<button 
	id="restart" 
    onclick="myVar = setInterval(myTimer, 100);
    document.getElementById('restart').style.display='none';
    document.getElementById('stop').style.display='block';" 
    style="display:none;"
>Restart time</button>