Answers for "how to get seconds in javascript"

js get current seconds

// Rounds the value
const timestamp = Math.round(new Date() / 1000); // 1405792937

// - OR -

// Floors the value
const timestamp = new Date() / 1000 | 0; // 1405792936

how to count seconds in javascript

var seconds = 0;
var el = document.getElementById('seconds-counter');

function incrementSeconds() {
    seconds += 1;
    el.innerText = "You have been here for " + seconds + " seconds.";
}

var cancel = setInterval(incrementSeconds, 1000);

js get current seconds

const timestamp = new Date() / 1000; // 1405792936.933
// Technically, .933 would be milliseconds.