Calculating milliseconds from epoch

Question

Given that I have: mm, dd, yy, hh:mm, am/pm, what is the recommended/easiest way to convert that data into milliseconds from epoch?

Answer 1

Everytime I get an upvote on this answer, I'm reminded that my answer doesn't actually answer the question.

OP: If you can parse your string into the following format, you can use one of the other answers. MM/DD/YYYY HH:MM:SS AM EDT (It's important to specify the timezone; epoch is based on the meridian)

let milliseconds = new Date("1/20/1982 5:00 PM EST").getTime()
console.log(milliseconds);

Original Answer that some people have found useful: Another technique (which most browsers support, as well as NodeJS) that doesn't require having to instantiate a Date object

var nowEpoch = Date.now();

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date

Answer 2

new Date("some string").getTime()

Answer 3

You can get the milliseconds from epoch with +new Date('date string').

jsFiddle.

The + operator implicitly calls valueOf() which returns the same as getTime().

Answer 4

var date;

if(pm)
    date = new Date(yy, mm, dd, hh+12, mm, 0, 0);
else
    date = new Date(yy, mm, dd, hh, mm, 0, 0);

var millis = date.getTime();
var seconds = millis/1000;

Answer 5

var myDate = new Date(Timestamp); // Your timezone! either timestamp ot date var myEpoch = myDate.getTime()/1000.0;