Date/Time Functions

checkdate — Validate a Gregorian date
date_add — Alias of DateTime::add
date_create_from_format — Alias of DateTime::createFromFormat
date_create_immutable_from_format — Alias of DateTimeImmutable::createFromFormat
date_create_immutable — Alias of DateTimeImmutable::__construct
date_create — Alias of DateTime::__construct
date_date_set — Alias of DateTime::setDate
date_default_timezone_get — Gets the default timezone used by all date/time functions in a script
date_default_timezone_set — Sets the default timezone used by all date/time functions in a script
date_diff — Alias of DateTime::diff
date_format — Alias of DateTime::format
date_get_last_errors — Alias of DateTime::getLastErrors
date_interval_create_from_date_string — Alias of DateInterval::createFromDateString
date_interval_format — Alias of DateInterval::format
date_isodate_set — Alias of DateTime::setISODate
date_modify — Alias of DateTime::modify
date_offset_get — Alias of DateTime::getOffset
date_parse_from_format — Get info about given date formatted according to the specified format
date_parse — Returns associative array with detailed info about given date
date_sub — Alias of DateTime::sub
date_sun_info — Returns an array with information about sunset/sunrise and twilight begin/end
date_sunrise — Returns time of sunrise for a given day and location
date_sunset — Returns time of sunset for a given day and location
date_time_set — Alias of DateTime::setTime
date_timestamp_get — Alias of DateTime::getTimestamp
date_timestamp_set — Alias of DateTime::setTimestamp
date_timezone_get — Alias of DateTime::getTimezone
date_timezone_set — Alias of DateTime::setTimezone
date — Format a local time/date
getdate — Get date/time information
gettimeofday — Get current time
gmdate — Format a GMT/UTC date/time
gmmktime — Get Unix timestamp for a GMT date
gmstrftime — Format a GMT/UTC time/date according to locale settings
idate — Format a local time/date as integer
localtime — Get the local time
microtime — Return current Unix timestamp with microseconds
mktime — Get Unix timestamp for a date
strftime — Format a local time/date according to locale settings
strptime — Parse a time/date generated with strftime
strtotime — Parse about any English textual datetime description into a Unix timestamp
time — Return current Unix timestamp
timezone_abbreviations_list — Alias of DateTimeZone::listAbbreviations
timezone_identifiers_list — Alias of DateTimeZone::listIdentifiers
timezone_location_get — Alias of DateTimeZone::getLocation
timezone_name_from_abbr — Returns the timezone name from abbreviation
timezone_name_get — Alias of DateTimeZone::getName
timezone_offset_get — Alias of DateTimeZone::getOffset
timezone_open — Alias of DateTimeZone::__construct
timezone_transitions_get — Alias of DateTimeZone::getTransitions
timezone_version_get — Gets the version of the timezonedb

User Contributed Notes

8 years ago


Not really elegant, but tells you, if your installed timezonedb is the most recent:



<?php

class TestDateTimeTimezonedbVersion extends PHPUnit_Framework_TestCase

{

    public function testTimezonedbIsMostRecent()

    {

        ini_set( 'date.timezone', 'Europe/Berlin' );

        ob_start();                                                                                                        

        phpinfo(INFO_MODULES);

        $info = ob_get_contents();                                                                                         

        ob_end_clean(); 

        $start = strpos( $info, 'Timezone Database Version' ) + 29;



        $this->assertTrue( FALSE !== $start, 'Seems there is no timezone DB installed' );



        $end   = strpos( $info, "\n", $start );

        $installedVersion = substr( $info, $start, $end - $start );



        exec( 'pecl remote-info timezonedb', &$output );

        $availableVersion = substr( $output[2], 12 );



        $this->assertEquals( $availableVersion, $installedVersion, 

        'The installed timezonedb is not actual. Installed: '.$installedVersion

        .' available: '.$availableVersion

        );

    }

}

?>

mincklerstraat at softhome dot net

11 years ago


Before you get too advanced using date functions, be sure also to see the calendar functions at http://www.php.net/manual/en/ref.calendar.php .

bgold at matrix-consultants dot com

9 years ago


When debugging code that stores date/time values in a database, you may find yourself wanting to know the date/time that corresponds to a given unix timestamp, or the timestamp for a given date & time.



The following script will do the conversion either way.  If you give it a numeric timestamp, it will display the corresponding date and time.  If you give it a date and time (in almost any standard format), it will display the timestamp.



All conversions are done for your locale/time zone.



<?php

        while (true)

        {

                // Read a line from standard in.

                echo "enter time to convert: ";

                $inline = fgets(STDIN);

                $inline = trim($inline);

                if ($inline == "" || $inline == ".")

                        break;



                // See if the line is a date.

                $pos = strpos($inline, "/");

                if ($pos === false) {

                        // not a date, should be an integer.

                        $date = date("m/d/Y G:i:s", $inline);

                        echo "int2date: $inline -> $date\n";

                } else {

                        $itime = strtotime($inline);

                        echo "date2int: $inline -> $itime\n";

                }

        }

?>

venoel at rin dot ru

8 years ago


May be useful for somebody. This function takes on daylight saving time



<?php

Function DateDiff($date1,$date2) {

  $timedifference=$date2-$date1;

  $corr=date("I",$date2)-date("I",$date1);

  $timedifference+=$corr;

  return $timedifference;

}

?>



Example:



<?php

$d1=mktime(2,0,0,10,28,2007);

$d2=mktime(4,0,0,10,28,2007);

$period=DateDiff($d1,$d2);

printf("<br>%s",date("I d.m.Y H:i",$d1));

printf("<br>%u hour",$period/3600);

printf("<br>%s",date("I d.m.Y H:i",$d2));

?>



Getting 2 hour instead 3.

glashio at xs4all dot nl

10 years ago


Calculate Sum BusinessDays (Mon till Fri) between two date's :

<?php
function businessdays($begin, $end) {
    $rbegin = is_string($begin) ? strtotime(strval($begin)) : $begin;
    $rend = is_string($end) ? strtotime(strval($end)) : $end;
    if ($rbegin < 0 || $rend < 0)
        return 0;

    $begin = workday($rbegin, TRUE);
    $end = workday($rend, FALSE);

    if ($end < $begin) {
        $end = $begin;
        $begin = $end;
    }

    $difftime = $end - $begin;
    $diffdays = floor($difftime / (24 * 60 * 60)) + 1;

    if ($diffdays < 7) {
        $abegin = getdate($rbegin);
        $aend = getdate($rend);
        if ($diffdays == 1 && ($astart['wday'] == 0 || $astart['wday'] == 6) && ($aend['wday'] == 0 || $aend['wday'] == 6))
            return 0;
        $abegin = getdate($begin);
        $aend = getdate($end);
        $weekends = ($aend['wday'] < $abegin['wday']) ? 1 : 0;
    } else
        $weekends = floor($diffdays / 7);
    return $diffdays - ($weekends * 2);
}

function workday($date, $begindate = TRUE) {
    $adate = getdate($date);
    $day = 24 * 60 * 60;
    if ($adate['wday'] == 0) // Sunday
        $date += $begindate ? $day : -($day * 2);
    elseif ($adate['wday'] == 6) // Saterday
        $date += $begindate ? $day * 2 : -$day;
    return $date;
}
?>

php-contrib at i-ps dot nospam dot net

14 years ago


Someone may find this info of some use:

Rules for calculating a leap year:

1) If the year divides by 4, it is a leap year (1988, 1992, 1996 are leap years)
2) Unless it divides by 100, in which case it isn't (1900 divides by 4, but was not a leap year)
3) Unless it divides by 400, in which case it is actually a leap year afterall (So 2000 was a leap year).

In practical terms, to work out the number of days in X years, multiply X by 365.2425, rounding DOWN to the last whole number, should give you the number of days.

The result will never be more than one whole day inaccurate, as opposed to multiplying by 365, which, over more years, will create a larger and larger deficit.

mail at completeideas dot com

10 years ago


For those who are using pre MYSQL 4.1.1, you can use:

TO_DAYS([Date Value 1])-TO_DAYS([Date Value 2])

For the same result as:

DATEDIFF([Date Value 1],[Date Value 2])

nightowl at NOS-PA-M dot uk2 dot net

13 years ago


I wanted to find all records in my database which match the current week (for a call-back function). I made up this function to find the start and end of the current week : 



<?php

function week($curtime) {

    

    $date_array = getdate (time());

    $numdays = $date_array["wday"];

    

    $startdate = date("Y-m-d", time() - ($numdays * 24*60*60));

    $enddate = date("Y-m-d", time() + ((7 - $numdays) * 24*60*60));



    $week['start'] = $startdate;

    $week['end'] = $enddate;

    

    return $week;

    

}

?>

daniel at globalnetstudios dot com

10 years ago


This dateDiff() function can take in just about any timestamp, including UNIX timestamps and anything that is accepted by strtotime(). It returns an array with the ability to split the result a couple different ways. I built this function to suffice any datediff needs I had. Hope it helps others too.

<?php
  /********* dateDiff() function **********
   * returns Array of Int values for difference between two dates
   * $date1 > $date2 --> positive integers are returned
   * $date1 < $date2 --> negative integers are returned
   *
   * $split recognizes the following:
   *   'yw' = splits up years, weeks and days (default)
   *   'y'  = splits up years and days
   *   'w'  = splits up weeks and days
   *   'd'  = total days
   *
   * examples:
   *   $dif1 = dateDiff() or dateDiff('yw')
   *   $dif2 = dateDiff('y')
   *   $dif3 = dateDiff('w')
   *   $dif4 = dateDiff('d')
   *
   * assuming dateDiff returned 853 days, the above
   * examples would have a print_r output of:
   *   $dif1 == Array( [y] => 2 [w] => 17 [d] => 4 )
   *   $dif2 == Array( [y] => 2 [d] => 123 )
   *   $dif3 == Array( [w] => 121 [d] => 6 )
   *   $dif4 == Array( [d] => 847 )
   *
   * note: [h] (hours), [m] (minutes), [s] (seconds) are always returned as elements of the Array
   */
  function dateDiff($dt1, $dt2, $split='yw') {
    $date1 = (strtotime($dt1) != -1) ? strtotime($dt1) : $dt1;
    $date2 = (strtotime($dt2) != -1) ? strtotime($dt2) : $dt2;
    $dtDiff = $date1 - $date2;
    $totalDays = intval($dtDiff/(24*60*60));
    $totalSecs = $dtDiff-($totalDays*24*60*60);
    $dif['h'] = $h = intval($totalSecs/(60*60));
    $dif['m'] = $m = intval(($totalSecs-($h*60*60))/60);
    $dif['s'] = $totalSecs-($h*60*60)-($m*60);
    // set up array as necessary
    switch($split) {
    case 'yw': # split years-weeks-days
      $dif['y'] = $y = intval($totalDays/365);
      $dif['w'] = $w = intval(($totalDays-($y*365))/7);
      $dif['d'] = $totalDays-($y*365)-($w*7);
      break;
    case 'y': # split years-days
      $dif['y'] = $y = intval($totalDays/365);
      $dif['d'] = $totalDays-($y*365);
      break;
    case 'w': # split weeks-days
      $dif['w'] = $w = intval($totalDays/7);
      $dif['d'] = $totalDays-($w*7);
      break;
    case 'd': # don't split -- total days
      $dif['d'] = $totalDays;
      break;
    default:
      die("Error in dateDiff(). Unrecognized \$split parameter. Valid values are 'yw', 'y', 'w', 'd'. Default is 'yw'.");
    }
    return $dif;
  }
?>

garyc at earthling dot net

13 years ago


I needed to calculate the week number from a given date and vice versa, where the week starts with a Monday and the first week of a year may begin the year before, if the year begins in the middle of the week (Tue-Sun). This is the way weekly magazines calculate their issue numbers.



Here are two functions that do exactly that:



Hope somebody finds this useful.



Gary



<?php

/*  w e e k n u m b e r  -------------------------------------- //

weeknumber returns a week number from a given date (>1970, <2030)

Wed, 2003-01-01 is in week 1

Mon, 2003-01-06 is in week 2

Wed, 2003-12-31 is in week 53, next years first week

Be careful, there are years with 53 weeks.

// ------------------------------------------------------------ */ 



function weeknumber ($y, $m, $d) {

    $wn = strftime("%W",mktime(0,0,0,$m,$d,$y));

    $wn += 0; # wn might be a string value

    $firstdayofyear = getdate(mktime(0,0,0,1,1,$y));

    if ($firstdayofyear["wday"] != 1)    # if 1/1 is not a Monday, add 1

        $wn += 1;

    return ($wn);

}    # function weeknumber



/*  d a t e f r o m w e e k  ---------------------------------- //

From a weeknumber, calculates the corresponding date

Input: Year, weeknumber and day offset

Output: Exact date in an associative (named) array

2003, 12, 0: 2003-03-17 (a Monday)

1995,  53, 2: 1995-12-xx

...

// ------------------------------------------------------------ */ 



function datefromweek ($y, $w, $o) {



    $days = ($w - 1) * 7 + $o;



    $firstdayofyear = getdate(mktime(0,0,0,1,1,$y));

    if ($firstdayofyear["wday"] == 0) $firstdayofyear["wday"] += 7; 

# in getdate, Sunday is 0 instead of 7

    $firstmonday = getdate(mktime(0,0,0,1,1-$firstdayofyear["wday"]+1,$y));

    $calcdate = getdate(mktime(0,0,0,$firstmonday["mon"], $firstmonday["mday"]+$days,$firstmonday["year"]));



    $date["year"] = $calcdate["year"];

    $date["month"] = $calcdate["mon"];

    $date["day"] = $calcdate["mday"];



    return ($date);



}    # function datefromweek

?>

brighn (a) yahoo (.) com

13 years ago


I needed a function that determined the last Sunday of the month. Since it's made for the website's "next meeting" announcement, it goes based on the system clock; also, if today is between Sunday and the end of the month, it figures out the last Sunday of *next* month. lastsunday() takes no arguments and returns the date as a string in the form "January 26, 2003". I could probably have streamlined this quite a bit, but at least it's transparent code. =)



<?php

  /* The two functions calculate when the next meeting will

     be, based on the assumption that the meeting will be on

     the last Sunday of the month. */  



  function getlast($mon, $year) {

    $daysinmonth = array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);

    $days = $daysinmonth[$mon-1];

    if ($mon == 2 && ($year % 4) == 0 && (($year % 100) != 0 ||

    ($year % 400) == 0)) $days++;

    if ($mon == 2 && ($year % 4) == 0 && ($year % 1000) != 0) $days++;

    $lastday = getdate(mktime(0,0,0,$mon,$days,$year));

    $wday = $lastday['wday'];

    return getdate(mktime(0,0,0,$mon,$days-$wday,$year));

  }



  function lastsunday() {

    $today = getdate();

    $mon = $today['mon'];

    $year = $today['year'];

    $mday = $today['mday'];

    $lastsun = getlast($mon, $year);

    $sunday = $lastsun['mday'];

    if ($sunday < $mday) {

      $mon++;

      if ($mon = 13) {

        $mon = 1;

        $year++;

      }

      $lastsun = getlast($mon, $year);

      $sunday = $lastsun['mday'];

    }

    $nextmeeting = getdate(mktime(0,0,0,$mon,$sunday,$year));

    $month = $nextmeeting['month'];

    $mday = $nextmeeting['mday'];

    $year = $nextmeeting['year'];

    return "$month $mday, $year";

  }

?>

andreencinas at yahoo dot com dot br

10 years ago


<?php

       //function like dateDiff Microsoft

       //not error in year Bissesto



       function dateDiff($interval,$dateTimeBegin,$dateTimeEnd) {

         //Parse about any English textual datetime

         //$dateTimeBegin, $dateTimeEnd



         $dateTimeBegin=strtotime($dateTimeBegin);

         if($dateTimeBegin === -1) {

           return("..begin date Invalid");

         }



         $dateTimeEnd=strtotime($dateTimeEnd);

         if($dateTimeEnd === -1) {

           return("..end date Invalid");

         }



         $dif=$dateTimeEnd - $dateTimeBegin;



         switch($interval) {

           case "s"://seconds

               return($dif);



           case "n"://minutes

               return(floor($dif/60)); //60s=1m



           case "h"://hours

               return(floor($dif/3600)); //3600s=1h



           case "d"://days

               return(floor($dif/86400)); //86400s=1d



           case "ww"://Week

               return(floor($dif/604800)); //604800s=1week=1semana



           case "m": //similar result "m" dateDiff Microsoft

               $monthBegin=(date("Y",$dateTimeBegin)*12)+

                 date("n",$dateTimeBegin);

               $monthEnd=(date("Y",$dateTimeEnd)*12)+

                 date("n",$dateTimeEnd);

               $monthDiff=$monthEnd-$monthBegin;

               return($monthDiff);



           case "yyyy": //similar result "yyyy" dateDiff Microsoft

               return(date("Y",$dateTimeEnd) - date("Y",$dateTimeBegin));



           default:

               return(floor($dif/86400)); //86400s=1d

         }



       }

?>

Hans

4 years ago


I needed a way to display an announcement on a shopping site, that would warn users that orders placed between a certain date range, would not be shipped until after a certain date.

I created this simple date detection code to display the notice on certain pages. You can just copy the code and save it to a file on the site and include it anywhere you need to perform a function, or display a notice.

<?php
/*
    Code to show a message only for a certain time frame.
    This is a simple include file that can be used to display a message
    on any pages that use it.
    Simply us a standard include instruction to this file on the page/s where 
    you want the notice to appear.
    Written by Hans Kiesouw - hans at wotworx dot com
*/

$start = new DateTime('30-07-2011'); // DD-MM-YYYY
$endDate= new DateTime('07-08-2011'); // DD-MM-YYYY
$curdate = new DateTime(date('d-m-Y'));

if ($start <= $curdate && $curdate <= $endDate) {
    /*
    The message below will appear if the current date is between the start and 
    endDate - used standards HTML to ensure that any code will not be 
    escaped by PHP. You can use any code here to wish to execute for the 
    date range.
    */
    ?>
    
    <p><strong><font color="#FF0000">Please Note: Any orders placed between July 30th and August 7th will only be shipped on August 8th. We apologize for any inconvenience and thank you for your order.</font></strong></p>
 <?php  
 // don't forget this last bit, it ends the if statement!
} 

?>

Robb_Bean at gmx dot nospam dot net

8 years ago


With PHP 5.1 and 5.2 the languages datetime support has changed. Although these functions should guess your local timezone settings, they may fail if using a default configuration in a "pre-5.1 way", which means setting no timezone for PHP. In the case PHP could not get a timezone it emits a E_STRICT warning. Note that this affects _all_ datetime functions and keep it in mind when porting software from previous versions to 5.1 or later! It may also confuse your error handling (this is the way I noticed that things have changed, since these changes are not documentated _here_).

References:

http://www.php.net/manual/de/migration51.datetime.php
http://www.php.net/manual/de/migration52.datetime.php

Darren Edwards

8 years ago


I was looking for a solution where I could return the number of days, hours, Minutes and seconds between two entries in a table.
DATE_DIFF is not running on my mysql server as my provider uses mysql version 4.0.25
Solution was to use to days and std time functions to calculate the difference in one call.
The fields stored in the table(report_table) are 
time(00:00:00),
date(0000-00-00) and record(enum) which tells the app the type of log stored. EG start or end of a report.

SELECT 
(TO_DAYS( `end`.`date` ) - TO_DAYS( `start`.`date` )) 
- 
( second( `end`.`time` ) + (minute( `end`.`time` )*60) + (hour( `end`.`time` )*3600) 
<
 second( `start`.`time` ) + (minute( `start`.`time` )*60) + (hour( `start`.`time` )*3600)) 
AS `days` , 
SEC_TO_TIME( 
(second( `end`.`time` ) + (minute( `end`.`time` )*60) + (hour( `end`.`time` )*3600) )
-
(second( `start`.`time` ) + (minute( `start`.`time` )*60) + (hour( `start`.`time` )*3600) )
 ) AS `hms`,
`start`.`time` as `start`,
`end`.`time`  as `end`

FROM `report_table` AS `start` , `report_table` AS `end` 
AND `start`.`record` = 'Report Begin'
AND `end`.`record` = 'Report End'
LIMIT 1 

If there is no end of report then it will not return a result, as you would expect.

Leopoldo A dot Oducado (poducado at comfsm dot fm)

9 years ago


Here is my function to count the number days, weeks, months, and year. I tried it below 1970 and it works.

<?php
function datecal($date,$return_value)
{
$date = explode("/", $date);
$month_begin = $date[0];
$month_begin_date = $date[1];
$year1 = $date[2];
$month_end = date("n");
$month_end_date = date("j");
$year2 = date("Y");
$days_old = 0;
$years_old = 0;
$months_old = 0;
if($month_begin==12)
{
  $month = 1;
  $year = $year1+1;
}
else
{
  $month = $month_begin+1;
  $year = $year1;
}
$begin_plus_days = cal_days_in_month(CAL_GREGORIAN, $month_begin, $year1) - $month_begin_date;
$end_minus_days = cal_days_in_month(CAL_GREGORIAN, $month_end, $year2) - $month_end_date;
while ($year <= $year2) 
{    
     if($year == $year2)
    {
      $days_old = $days_old + cal_days_in_month(CAL_GREGORIAN, $month, $year);     
      if($month < $month_end)
        { 
         $months_old = $months_old + 1;    
         $month = $month + 1;
        }
          elseif ($month==$month_end and $month_end_date >= $month_begin_date)
            { 
         $year = $year2+1;    
        }
      else
        {    
         $year = $year2+1;    
        }
    }
    else
    {
     $days_old = $days_old + cal_days_in_month(CAL_GREGORIAN, $month, $year);
         if ($month <= 11) 
            {
         $month = $month + 1;
         $months_old = $months_old + 1;    
            }
         else
            {
         $month = 1; 
         $year = $year + 1;
         $months_old = $months_old + 1;        
            }     
    }
}
$days_old = ($days_old + $begin_plus_days) - $end_minus_days;
if($return_value == "d")
  { return $days_old; }
elseif ($return_value == "w")
  { return intval($days_old/7); }
elseif ($return_value == "m")
  { return $months_old; }
elseif ($return_value == "y")
  { return intval($months_old/12); }
}

echo datecal("08/13/1975","m");
?>

nickaubert at america's biggest isp dot com

12 years ago


I ran into an issue using a function that loops through an array of dates where the keys to the array are the Unix timestamp for midnight for each date.  The loop starts at the first timestamp, then incremented by adding 86400 seconds (ie. 60 x 60 x 24).  However, Daylight Saving Time threw off the accuracy of this loop, since certain days have a duration other than 86400 seconds.  I worked around it by adding a couple of lines to force the timestamp to midnight at each interval.

<?php
  $ONE_DAY = 90000;   // can't use 86400 because some days have one hour more or less
  for ( $each_timestamp = $start_time ; $each_timestamp <= $end_time ; $each_timestamp +=  $ONE_DAY) {

    /*  force midnight to compensate for daylight saving time  */
    $this_timestamp_array = getdate( $each_timestamp );
    $each_timestamp = mktime ( 0 , 0 , 0 , $this_timestamp_array[mon] , $this_timestamp_array[mday] , $this_timestamp_array[year] );

     // do some stuff...
  }
?>

php at elmegil dot net

12 years ago


A much easier way to do days diff is to use Julian Days from the Calendar functions:

$start = gregoriantojd($smon, $sday, $syear);
$end = gregoriantojd($emon, $eday, $eyear);
$daysdiff = $end - $start;

You can see the obvious ways to wrap a function around that.

th at definitynet dot com

15 years ago


I had some problems with dates between mySQL and PHP.  PHP had all these great date functions but I wanted to store a usable value in my database tables. In this case I was using TIMESTAMP(14)  <or 'YYYYMMDDHHMMSS'>. 

This is perhaps the easiest way I have found to pull the PHP usable UNIX Datestamp from my mySQL datestamp stored in the tables:



Use the mySQL UNIX_TIMESTAMP() function in your SQL definition string. i.e.



$sql= "SELECT field1, field2, UNIX_TIMESTAMP(field3) as your_date

          FROM your_table

          WHERE field1 = '$value'";



The query will return a temp table with coulms "field1" "Field2" "your_date"



The "your_date" will be formatted in a UNIX TIMESTAMP!  Now you can use the PHP date() function to spew out nice date formats.



Sample using above $sql:

20010111002747  = Date Stored on mySQL table (TIMESTAMP(14))

979172867  = value returned as your_date in sql stmt (UNIX_TIMESTAMP)



if we use $newdate = date("F jS, Y -- g:ia", $row["your_date"]);

   --(after fetching our array from the sql results of course)--



echo "$newdate";              --Will produce:

January 11th, 2001 -- 12:27am



Hope this helps someone out there!

luck dot lil dot leprechaun at gmail dot com

6 years ago


This is an easily extendable and pretty way to output human-readable date differences such as "1 day 2 hours ago", "6 months ago", "3 years 7 months 14 days 1 hour 4 minutes 16 seconds" etc etc.

Change "$levels = 2;" to whatever you want. A value of 1 will limit to only one number in the result ("3 days ago"). A value of 3 would result in up to three ("3 days 1 hour 2 minutes ago")



It can be used in the following ways:

echo compare_dates($start_date,$end_date);

echo compare_dates($end_date,$start_date);

echo compare_dates($start_date); //end date will be assumed as time();



<?php

function compare_dates($date1, $date2 = time())

    {

    $blocks = array(

        array('name'=>'year','amount'    =>    60*60*24*365    ),

        array('name'=>'month','amount'    =>    60*60*24*31    ),

        array('name'=>'week','amount'    =>    60*60*24*7    ),

        array('name'=>'day','amount'    =>    60*60*24    ),

        array('name'=>'hour','amount'    =>    60*60        ),

        array('name'=>'minute','amount'    =>    60        ),

        array('name'=>'second','amount'    =>    1        )

        );

    

    $diff = abs($date1-$date2);

    

    $levels = 2;

    $current_level = 1;

    $result = array();

    foreach($blocks as $block)

        {

        if ($current_level > $levels) {break;}

        if ($diff/$block['amount'] >= 1)

            {

            $amount = floor($diff/$block['amount']);

            if ($amount>1) {$plural='s';} else {$plural='';}

            $result[] = $amount.' '.$block['name'].$plural;

            $diff -= $amount*$block['amount'];

            $current_level++;

            }

        }

    return implode(' ',$result).' ago';

    }

?>



[EDIT BY danbrown AT php DOT net: Contains a bugfix supplied by (jorge AT dontspam DOT com) on 22-OCT-2009.]

sagar

8 years ago


<?php

####################################

# Provide week number and get start_timestamp and end_timestamp

#####################################



// this week number will come from the timeshare form

 $week = 51;



$times = get_start_and_end_date_from_week($week);

$start_time = $times['start_timestamp'];

$end_time = $times['end_timestamp'];



function get_start_and_end_date_from_week ($w) 

{

    $y = date("Y", time());

    $o = 6; // week starts from sunday by default



    $days = ($w - 1) * 7 + $o;



    $firstdayofyear = getdate(mktime(0,0,0,1,1,$y));

    if ($firstdayofyear["wday"] == 0) $firstdayofyear["wday"] += 7;

    # in getdate, Sunday is 0 instead of 7

    $firstmonday = getdate(mktime(0,0,0,1,1-$firstdayofyear["wday"]+1,$y));

    $calcdate = getdate(mktime(0,0,0,$firstmonday["mon"], $firstmonday["mday"]+$days,$firstmonday["year"]));



    $sday = $calcdate["mday"];

    $smonth = $calcdate["mon"];

    $syear = $calcdate["year"];

    

        

    $timestamp['start_timestamp'] =  mktime(0, 0, 0, $smonth, $sday, $syear);

    $timestamp['end_timestamp'] =  $timestamp['start_timestamp'] + (60*60*24*7);



    return $timestamp;



}    # function datefromweek

?>

php at sarge dot ch

12 years ago


Additional thisone here (didn't test it yet but should work :D):

<?php
/**
 * Calculates the Difference between two timestamps
 *
 * @param integer $start_timestamp
 * @param integer $end_timestamp
 * @param integer $unit (default 0)
 * @return string
 * @access public
 */
function dateDifference($start_timestamp,$end_timestamp,$unit= 0){
  $days_seconds_star= (23 * 56 * 60) + 4.091; // Star Day
  $days_seconds_sun= 24 * 60 * 60; // Sun Day
  $difference_seconds= $end_timestamp - $start_timestamp;
  switch($unit){
    case 3: // Days
      $difference_days= round(($difference_seconds / $days_seconds_sun),2);
      return 'approx. '.$difference_hours.' Days';
    case 2: // Hours
      $difference_hours= round(($difference_seconds / 3600),2);
      return 'approx. '.$difference_hours.' Hours';
    break;
    case 1: // Minutes
      $difference_minutes= round(($difference_seconds / 60),2);
      return 'approx. '.$difference_minutes.' Minutes';
    break;
    default: // Seconds
      if($difference_seconds > 1){
        return $difference_seconds.' Seconds';
      }
      else{
        return $difference_seconds.' Second';
      }
  }
}
?>

stoicnluv at gmail dot com

8 years ago


A better and accurate function to calculate the difference between 2 dates. Takes leap years and DST into consideration. Accepts string date or timestamp as arguments.

<?php
function date_diff($d1, $d2){
    $d1 = (is_string($d1) ? strtotime($d1) : $d1);
    $d2 = (is_string($d2) ? strtotime($d2) : $d2);

    $diff_secs = abs($d1 - $d2);
    $base_year = min(date("Y", $d1), date("Y", $d2));

    $diff = mktime(0, 0, $diff_secs, 1, 1, $base_year);
    return array(
        "years" => date("Y", $diff) - $base_year,
        "months_total" => (date("Y", $diff) - $base_year) * 12 + date("n", $diff) - 1,
        "months" => date("n", $diff) - 1,
        "days_total" => floor($diff_secs / (3600 * 24)),
        "days" => date("j", $diff) - 1,
        "hours_total" => floor($diff_secs / 3600),
        "hours" => date("G", $diff),
        "minutes_total" => floor($diff_secs / 60),
        "minutes" => (int) date("i", $diff),
        "seconds_total" => $diff_secs,
        "seconds" => (int) date("s", $diff)
    );
}

$a = date_diff("2006-11-01", "2007-11-01");

echo "<pre>";
print_r($a);
echo "</pre>";
?>

This example will output (if your timezone uses US DST):

Array
(
    [years] => 0
    [months_total] => 11
    [months] => 11
    [days_total] => 364
    [days] => 30
    [hours_total] => 8759
    [hours] => 23
    [minutes_total] => 525540
    [minutes] => 0
    [seconds_total] => 31532400
    [seconds] => 0
)

As you can see, the result is not exactly 1 year (less 1 hour) since Nov 1, 2006 is not DST while Nov 1, 2007 is DST.

aquatakat at telus dot net

8 years ago


I wrote a simple script to format a duration in seconds. Give the function some value in seconds and it will return an array.

<?php

function format_duration($seconds) {

    $periods = array(
        'centuries' => 3155692600,
        'decades' => 315569260,
        'years' => 31556926,
        'months' => 2629743,
        'weeks' => 604800,
        'days' => 86400,
        'hours' => 3600,
        'minutes' => 60,
        'seconds' => 1
    );

    $durations = array();

    foreach ($periods as $period => $seconds_in_period) {
        if ($seconds >= $seconds_in_period) {
            $durations[$period] = floor($seconds / $seconds_in_period);
            $seconds -= $durations[$period] * $seconds_in_period;
        }
    }
    
    return $durations;

}

echo format_duration(864);

/*
[minutes] => 14
[seconds] => 24
*/

echo format_duration(3600);

/*
[hours] => 1
*/

echo format_duration(11111111);

/*
[months] => 4
[days] => 6
[hours] => 20
[minutes] => 28
[seconds] => 59
*/

?>

Date/Time Functions

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User Contributed Notes