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android java date difference in days

android java date difference in days  using -'java,android,date'

I am getting the current date (in format 12/31/1999 i.e. mm/dd/yyyy) as using the below code:

Textview txtViewData;
txtViewDate.setText("Today is " +
        android.text.format.DateFormat.getDateFormat(this).format(new Date()));

and I am having another date in format as: 2010-08-25 (i.e. yyyy/mm/dd) ,

so I want to find the difference between date in number of days, how do I find difference in days?

(In other words, I want to find the difference between CURRENT DATE - yyyy/mm/dd formatted date)

asked Sep 10, 2015 by DilZVKM
0 votes

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11 Answers

0 votes

Not really a reliable method, better of using JodaTime

  Calendar thatDay = Calendar.getInstance();
  thatDay.set(Calendar.MONTH,7); // 0-11 so 1 less
  thatDay.set(Calendar.YEAR, 1985);

  Calendar today = Calendar.getInstance();

  long diff = today.getTimeInMillis() - thatDay.getTimeInMillis(); //result in millis

Here's an approximation...

long days = diff / (24 * 60 * 60 * 1000);

To Parse the date from a string, you could use

  String strThatDay = "1985/08/25";
  SimpleDateFormat formatter = new SimpleDateFormat("yyyy/MM/dd");
  Date d = null;
  try {
   d = formatter.parse(strThatDay);//catch exception
  } catch (ParseException e) {
   // TODO Auto-generated catch block

  Calendar thatDay = Calendar.getInstance();
  thatDay.setTime(d); //rest is the same....

Although, since you're sure of the date format... You Could also do Integer.parseInt() on it's Substrings to obtain their numeric values.

Can anyone further tell me how to tell user the number of days left for him to return books - in android programming (Java) - any help will be appreciated.

answered Sep 10, 2015 by A6907
0 votes

This is NOT my work, found the answer here. did not want a broken link in the future :).

The key is this line for taking daylight setting into account, ref Full Code.


or try passing TimeZone as a parameter to daysBetween() and call setTimeZone() in the sDate and eDate objects.

So here it goes:

public static Calendar getDatePart(Date date){
    Calendar cal = Calendar.getInstance();       // get calendar instance
    cal.set(Calendar.HOUR_OF_DAY, 0);            // set hour to midnight
    cal.set(Calendar.MINUTE, 0);                 // set minute in hour
    cal.set(Calendar.SECOND, 0);                 // set second in minute
    cal.set(Calendar.MILLISECOND, 0);            // set millisecond in second

    return cal;                                  // return the date part

getDatePart() taken from here

 * This method also assumes endDate >= startDate
public static long daysBetween(Date startDate, Date endDate) {
  Calendar sDate = getDatePart(startDate);
  Calendar eDate = getDatePart(endDate);

  long daysBetween = 0;
  while (sDate.before(eDate)) {
      sDate.add(Calendar.DAY_OF_MONTH, 1);
  return daysBetween;

The Nuances: Finding the difference between two dates isn't as straightforward as subtracting the two dates and dividing the result by (24 * 60 * 60 * 1000). Infact, its erroneous!

For example: The difference between the two dates 03/24/2007 and 03/25/2007 should be 1 day; However, using the above method, in the UK, you'll get 0 days!

See for yourself (code below). Going the milliseconds way will lead to rounding off errors and they become most evident once you have a little thing like Daylight Savings Time come into the picture.

Full Code:

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

public class DateTest {

public class DateTest {

static SimpleDateFormat sdf = new SimpleDateFormat("dd-MMM-yyyy");

public static void main(String[] args) {


  //diff between these 2 dates should be 1
  Date d1 = new Date("01/01/2007 12:00:00");
  Date d2 = new Date("01/02/2007 12:00:00");

  //diff between these 2 dates should be 1
  Date d3 = new Date("03/24/2007 12:00:00");
  Date d4 = new Date("03/25/2007 12:00:00");

  Calendar cal1 = Calendar.getInstance();cal1.setTime(d1);
  Calendar cal2 = Calendar.getInstance();cal2.setTime(d2);
  Calendar cal3 = Calendar.getInstance();cal3.setTime(d3);
  Calendar cal4 = Calendar.getInstance();cal4.setTime(d4);

  printOutput("Manual   ", d1, d2, calculateDays(d1, d2));
  printOutput("Calendar ", d1, d2, daysBetween(cal1, cal2));
  printOutput("Manual   ", d3, d4, calculateDays(d3, d4));
  printOutput("Calendar ", d3, d4, daysBetween(cal3, cal4));

private static void printOutput(String type, Date d1, Date d2, long result) {
  System.out.println(type+ "- Days between: " + sdf.format(d1)
                    + " and " + sdf.format(d2) + " is: " + result);

/* This method is used to find the no of days between the given dates */
public static long calculateDays(Date dateEarly, Date dateLater) {
  return (dateLater.getTime() - dateEarly.getTime()) / (24 * 60 * 60 * 1000);

/** Using Calendar - THE CORRECT WAY**/
public static long daysBetween(Date startDate, Date endDate) {


Manual - Days between: 01-Jan-2007 and 02-Jan-2007 is: 1

Calendar - Days between: 01-Jan-2007 and 02-Jan-2007 is: 1

Manual - Days between: 24-Mar-2007 and 25-Mar-2007 is: 0

Calendar - Days between: 24-Mar-2007 and 25-Mar-2007 is: 1

answered Sep 10, 2015 by KandiO36bytq
0 votes

Use jodatime API

Days.daysBetween(start.toDateMidnight() , end.toDateMidnight() ).getDays() 

where 'start' and 'end' are your DateTime objects. To parse your date Strings into DateTime objects use the parseDateTime method

answered Sep 10, 2015 by BobReymond
0 votes

Most of the answers were good and right for your problem of

so i want to find the difference between date in number of days, how do i find difference in days?

I suggest this very simple and straightforward approach that is guaranteed to give you the correct difference in any time zone:

int difference= 

And that's it!

answered Sep 10, 2015 by Glo30N
0 votes

This fragment accounts for daylight savings time and is O(1).

private final static long MILLISECS_PER_DAY = 24 * 60 * 60 * 1000;

private static long getDateToLong(Date date) {
    return Date.UTC(date.getYear(), date.getMonth(), date.getDate(), 0, 0, 0);

public static int getSignedDiffInDays(Date beginDate, Date endDate) {
    long beginMS = getDateToLong(beginDate);
    long endMS = getDateToLong(endDate);
    long diff = (endMS - beginMS) / (MILLISECS_PER_DAY);
    return (int)diff;

public static int getUnsignedDiffInDays(Date beginDate, Date endDate) {
    return Math.abs(getSignedDiffInDays(beginDate, endDate));
answered Sep 10, 2015 by CelesteXgyj
0 votes

The Correct Way from Sam Quest's answer only works if the first date is earlier than the second. Moreover, it will return 1 if the two dates are within a single day.

This is the solution that worked best for me. Just like most other solutions, it would still show incorrect results on two days in a year because of wrong day light saving offset.

private final static long MILLISECS_PER_DAY = 24 * 60 * 60 * 1000;

long calculateDeltaInDays(Calendar a, Calendar b) {

    // Optional: avoid cloning objects if it is the same day
    if(a.get(Calendar.ERA) == b.get(Calendar.ERA) 
            && a.get(Calendar.YEAR) == b.get(Calendar.YEAR)
            && a.get(Calendar.DAY_OF_YEAR) == b.get(Calendar.DAY_OF_YEAR)) {
        return 0;
    Calendar a2 = (Calendar) a.clone();
    Calendar b2 = (Calendar) b.clone();
    a2.set(Calendar.HOUR_OF_DAY, 0);
    a2.set(Calendar.MINUTE, 0);
    a2.set(Calendar.SECOND, 0);
    a2.set(Calendar.MILLISECOND, 0);
    b2.set(Calendar.HOUR_OF_DAY, 0);
    b2.set(Calendar.MINUTE, 0);
    b2.set(Calendar.SECOND, 0);
    b2.set(Calendar.MILLISECOND, 0);
    long diff = a2.getTimeInMillis() - b2.getTimeInMillis();
    long days = diff / MILLISECS_PER_DAY;
    return Math.abs(days);
answered Sep 10, 2015 by FraBaker
0 votes

Use the following functions:

     * Returns the number of days between two dates. The time part of the
     * days is ignored in this calculation, so 2007-01-01 13:00 and 2007-01-02 05:00
     * have one day inbetween.
    public static long daysBetween(Date firstDate, Date secondDate) {
        // We only use the date part of the given dates
        long firstSeconds = truncateToDate(firstDate).getTime()/1000;
        long secondSeconds = truncateToDate(secondDate).getTime()/1000;
        // Just taking the difference of the millis.
        // These will not be exactly multiples of 24*60*60, since there
        // might be daylight saving time somewhere inbetween. However, we can
        // say that by adding a half day and rounding down afterwards, we always
        // get the full days.
        long difference = secondSeconds-firstSeconds;
        // Adding half a day
        if( difference >= 0 ) {
            difference += SECONDS_PER_DAY/2; // plus half a day in seconds
        } else {
            difference -= SECONDS_PER_DAY/2; // minus half a day in seconds
        // Rounding down to days
        difference /= SECONDS_PER_DAY;

        return difference;

     * Truncates a date to the date part alone.
    public static Date truncateToDate(Date d) {
        if( d instanceof java.sql.Date ) {
            return d; // java.sql.Date is already truncated to date. And raises an
                      // Exception if we try to set hours, minutes or seconds.
        d = (Date)d.clone();
        return d;
answered Sep 10, 2015 by KatChiles
0 votes

There's a simple solution, that at least for me, is the only feasible solution.

The problem is that all the answers I see being tossed around - using Joda, or Calendar, or Date, or whatever - only take the amount of milliseconds into consideration. They end up counting the number of 24-hour cycles between two dates, rather than the actual number of days. So something from Jan 1st 11pm to Jan 2nd 1am will return 0 days.

To count the actual number of days between startDate and endDate, simply do:

// Find the sequential day from a date, essentially resetting time to start of the day
long startDay = startDate.getTime() / 1000 / 60 / 60 / 24;
long endDay = endDate.getTime() / 1000 / 60 / 60 / 24;

// Find the difference, duh
long daysBetween = endDay - startDay;

This will return "1" between Jan 2nd and Jan 1st. If you need to count the end day, just add 1 to daysBetween (I needed to do that in my code since I wanted to count the total number of days in the range).

This is somewhat similar to what Daniel has suggested but smaller code I suppose.

answered Sep 10, 2015 by Lor5416
0 votes

This is Simple and best calculation for me and may be for you.

       try {
            /// String CurrDate=  "10/6/2013";
            /// String PrvvDate=  "10/7/2013";
            Date date1 = null;
            Date date2 = null;
            SimpleDateFormat df = new SimpleDateFormat("M/dd/yyyy");
            date1 = df.parse(CurrDate);
            date2 = df.parse(PrvvDate);
            long diff = Math.abs(date1.getTime() - date2.getTime());
            long diffDays = diff / (24 * 60 * 60 * 1000);


        } catch (Exception e1) {
            System.out.println("exception " + e1);
answered Sep 10, 2015 by SungChisholm
0 votes

I found a very easy way to do this and it's what I'm using in my app.

Let's say you have the dates in Time objects (or whatever, we just need the milliseconds):

Time date1 = initializeDate1(); //get the date from somewhere
Time date2 = initializeDate2(); //get the date from somewhere

long millis1 = date1.toMillis(true);
long millis2 = date2.toMillis(true);

long difference = millis2 - millis1 ;

//now get the days from the difference and that's it
long days = TimeUnit.MILLISECONDS.toDays(difference);

//now you can do something like
if(days == 7)
    //do whatever when there's a week of difference

if(days >= 30)
    //do whatever when it's been a month or more
answered Sep 10, 2015 by GeraldCherry
0 votes

All of these solutions suffer from one of two problems. Either the solution isn't perfectly accurate due to rounding errors, leap days and seconds, etc. or you end up looping over the number of days in between your two unknown dates.

This solution solves the first problem, and improves the second by a factor of roughly 365, better if you know what your max range is.

 * @param thisDate
 * @param thatDate
 * @param maxDays
 *            set to -1 to not set a max
 * @returns number of days covered between thisDate and thatDate, inclusive, i.e., counting both
 *          thisDate and thatDate as an entire day. Will short out if the number of days exceeds
 *          or meets maxDays
public static int daysCoveredByDates(Date thisDate, Date thatDate, int maxDays) {
    //Check inputs
    if (thisDate == null || thatDate == null) {
        return -1;

    //Set calendar objects
    Calendar startCal = Calendar.getInstance();
    Calendar endCal = Calendar.getInstance();
    if (thisDate.before(thatDate)) {
    else {

    //Get years and dates of our times.
    int startYear = startCal.get(Calendar.YEAR);
    int endYear = endCal.get(Calendar.YEAR);
    int startDay = startCal.get(Calendar.DAY_OF_YEAR);
    int endDay = endCal.get(Calendar.DAY_OF_YEAR);

    //Calculate the number of days between dates.  Add up each year going by until we catch up to endDate.
    while (startYear < endYear && maxDays >= 0 && endDay - startDay + 1 < maxDays) {
        endDay += startCal.getActualMaximum(Calendar.DAY_OF_YEAR); //adds the number of days in the year startDate is currently in
        startCal.set(Calendar.YEAR, startYear); //reup the year
    int days = endDay - startDay + 1;

    //Honor the maximum, if set
    if (maxDays >= 0) {
        days = Math.min(days, maxDays);
    return days;

If you need days between dates (uninclusive of the latter date), just get rid of the + 1 when you see endDay - startDay + 1.

answered Sep 10, 2015 by RoseanneH011