Difference Between 2 Dates in Seconds

Get time difference between two dates in seconds

The Code

var startDate = new Date();
// Do your operations
var endDate   = new Date();
var seconds = (endDate.getTime() - startDate.getTime()) / 1000;

Or even simpler (endDate - startDate) / 1000 as pointed out in the comments unless you're using typescript.

The explanation

You need to call the getTime() method for the Date objects, and then simply subtract them and divide by 1000 (since it's originally in milliseconds). As an extra, when you're calling the getDate() method, you're in fact getting the day of the month as an integer between 1 and 31 (not zero based) as opposed to the epoch time you'd get from calling the getTime() method, representing the number of milliseconds since January 1st 1970, 00:00

Rant

Depending on what your date related operations are, you might want to invest in integrating a library such as date.js or moment.js which make things so much easier for the developer, but that's just a matter of personal preference.

For example in moment.js we would do moment1.diff(moment2, "seconds") which is beautiful.

Useful docs for this answer

Why 1970?
Date object
Date's getTime method
Date's getDate method
Need more accuracy than just seconds?

How do I check the difference, in seconds, between two dates?

if you want to compute differences between two known dates, use total_seconds like this:

import datetime as dt

a = dt.datetime(2013,12,30,23,59,59)
b = dt.datetime(2013,12,31,23,59,59)

(b-a).total_seconds()

86400.0

#note that seconds doesn't give you what you want:
(b-a).seconds

In Java, how do I get the difference in seconds between 2 dates?

Not familiar with DateTime...

If you have two Dates you can call getTime on them to get millseconds, get the diff and divide by 1000. For example

Date d1 = ...;
Date d2 = ...;
long seconds = (d2.getTime()-d1.getTime())/1000;

If you have Calendar objects you can call

c.getTimeInMillis()

and do the same

Difference between 2 dates in seconds

$timeFirst  = strtotime('2011-05-12 18:20:20');
$timeSecond = strtotime('2011-05-13 18:20:20');
$differenceInSeconds = $timeSecond - $timeFirst;

You will then be able to use the seconds to find minutes, hours, days, etc.

Android difference between two dates in seconds

You can turn a date object into a long (milliseconds since Jan 1, 1970), and then use TimeUnit to get the number of seconds:

long diffInMs = endDate.getTime() - startDate.getTime();

long diffInSec = TimeUnit.MILLISECONDS.toSeconds(diffInMs);

Edit:
-Corrected the name of the variable diffInMs which was written diffInM(i)s in the second line.

How do I calculate how many seconds between two dates?

I'm taking YYYY & ZZZZ to mean integer values which mean the year, MM & NN to mean integer values meaning the month of the year and DD & EE as integer values meaning the day of the month.

var t1 = new Date(YYYY, MM, DD, 0, 0, 0, 0);
var t2 = new Date(ZZZZ, NN, EE, 0, 0, 0, 0);
var dif = t1.getTime() - t2.getTime();

var Seconds_from_T1_to_T2 = dif / 1000;
var Seconds_Between_Dates = Math.abs(Seconds_from_T1_to_T2);

A handy source for future reference is the MDN site

Alternatively, if your dates come in a format javascript can parse

var dif = Date.parse(MM + " " + DD + ", " + YYYY) - Date.parse(NN + " " + EE + ", " + ZZZZ);

and then you can use that value as the difference in milliseconds (dif in both my examples has the same meaning)

Time difference in seconds between given two dates

Assuming GNU implementation based OS, you can use date's option %s and -d to calculate the time difference in seconds using command substitution and arithmetic operations.

START="2019-01-05 23:52:00"
END="2019-01-06 00:02:10"

Time_diff_in_secs=$(($(date -d "$END" +%s) - $(date -d "$START" +%s)))
echo $Time_diff_in_secs

Output:

Hope this helps!!!