# how to find number of mondays or tuesdays between two dates?

I have start date and end date.

I need to find out the day that is Sunday or Monday etc dependent upon user click on check box.

How can I find/calculate that in PHP?

I got the answer.Its working for sunday only.But I dont know how to make it for another days

"; \$days_until_sunday = date('w', \$start) > 0 ? 7 - date('w', \$start) : 0; \$date = \$start + (ONE_DAY * \$days_until_sunday); \$sundays = array(); while (\$date "; \$count=0; // Loop and output Y-m-d foreach (sundays_in_range(\$start, \$end) as \$sunday) { print "".date("Y-m-d", \$sunday)."
"; \$count++; } echo \$count; ?>

no loops and no recursivity

``````<?php
define('ONE_WEEK', 604800); // 7 * 24 * 60 * 60

function number_of_days(\$days, \$start, \$end) {
\$w = array(date('w', \$start), date('w', \$end));
\$x = floor((\$end-\$start)/ONE_WEEK);
\$sum = 0;

for (\$day = 0;\$day < 7;++\$day) {
if (\$days & pow(2, \$day)) {
\$sum += \$x + (\$w[0] > \$w[1]?\$w[0] <= \$day || \$day <= \$w[1] : \$w[0] <= \$day && \$day <= \$w[1]);
}
}

return \$sum;
}

//\$start = \$end = time();

// 0x10 == pow(2, 4) == 1 << 4 // THURSDAY
// 0x20 == pow(2, 5) == 1 << 5 // FRIDAY
echo number_of_days(0x01, \$start, \$end); // SUNDAY
echo number_of_days(pow(2, 0), \$start, \$end); // SUNDAY
echo number_of_days(0x02, \$start, \$end); // MONDAY
echo number_of_days(pow(2, 1), \$start, \$end); // MONDAY
echo number_of_days(0x04, \$start, \$end); // TUESDAY
echo number_of_days(1 << 2, \$start, \$end); // TUESDAY
echo number_of_days(0x08, \$start, \$end); // WEDNESDAY
echo number_of_days(1 << 3, \$start, \$end); // WEDNESDAY
echo number_of_days(0x10, \$start, \$end); // THURSDAY
echo number_of_days(0x20, \$start, \$end); // FRIDAY
echo number_of_days(0x40, \$start, \$end); // SATURDAY
echo number_of_days(0x01 | 0x40, \$start, \$end); // WEEKENDS : SUNDAY | SATURDAY
echo number_of_days(0x3E, \$start, \$end); // WORKDAYS : MONDAY | TUESDAY | WEDNESDAY | THURSDAY | FRIDAY
?>
``````

The answer by w35I3y was almost correct, but I was getting errors using that function. This function correctly calculates the number of Mondays or any specific day between two given dates:

``````/**
* Counts the number occurrences of a certain day of the week between a start and end date
* The \$start and \$end variables must be in UTC format or you will get the wrong number
* of days  when crossing daylight savings time
* @param - \$day - the day of the week such as "Monday", "Tuesday"...
* @param - \$start - a UTC timestamp representing the start date
* @param - \$end - a UTC timestamp representing the end date
* @return Number of occurences of \$day between \$start and \$end
*/
function countDays(\$day, \$start, \$end)
{
//get the day of the week for start and end dates (0-6)
\$w = array(date('w', \$start), date('w', \$end));

//get partial week day count
if (\$w[0] < \$w[1])
{
\$partialWeekCount = (\$day >= \$w[0] && \$day <= \$w[1]);
}else if (\$w[0] == \$w[1])
{
\$partialWeekCount = \$w[0] == \$day;
}else
{
\$partialWeekCount = (\$day >= \$w[0] || \$day <= \$w[1]);
}

//first count the number of complete weeks, then add 1 if \$day falls in a partial week.
return floor( ( \$end-\$start )/60/60/24/7) + \$partialWeekCount;
}
``````

Example Usage:

``````\$start = strtotime("tuesday UTC");
\$end = strtotime("3 tuesday UTC");
echo date("m/d/Y", \$start). " - ".date("m/d/Y", \$end). " has ". countDays(0, \$start, \$end). " Sundays";
``````

Outputs something like: 09/28/2010 - 10/19/2010 has 3 Sundays.

``````<?php
\$date = strtotime('2009-01-01');
\$dateMax = strtotime('2009-02-23');

\$nbr = 0;
while (\$date < \$dateMax) {
var_dump(date('Y-m-d', \$date));
\$nbr++;
\$date += 7 * 24 * 3600;
}
echo "<pre>";
var_dump(\$nbr);
?>
``````
``````function daycount(\$day, \$startdate, \$enddate, \$counter) {
if(\$startdate >= \$enddate) {
return \$counter-1;  // A hack to make this function return the correct number of days.
} else {
return \$this->daycount(\$day, strtotime("next ".\$day, \$startdate), \$enddate, ++\$counter);
}
}
``````

This is a different version of the first answer which takes a start and end point and works for me. All of the examples given on this page seemed to return the answer plus an additional day for some reason.

w35l3y's answer seems to work well, so I up-voted it. Still, I preferred something a bit easier to follow, and with less math and looping (not sure it matters from a performance standpoint, though). I think I covered all the possible scenarios... Here's what I came up with:

``````function numDays(\$sday, \$eday, \$i, \$cnt) {
if ((\$sday < \$eday && \$i >= \$sday && \$i <= \$eday) || (\$sday > \$eday && (\$i >= \$sday || \$i <= \$eday))) {
// partial week (implied by \$sday != \$eday), so \$i (day iteration) may have occurred one more time
// a) end day is ahead of start day; \$i is within start/end of week range
// b) start day is ahead of end day (i.e., Tue start, Sun end); \$i is either in back half of first week or front half of second week
\$cnt++;
} elseif (\$sday == \$eday && \$i == \$sday) {
// start day and end day are the same, and \$i is that day, i.e., Tue occurs twice from Tue-Tue (1 wk, so \$wks = \$cnt)
\$cnt++;
}

return \$cnt;    // # of complete weeks + partial week, if applicable
}
``````

Notes: \$sday and \$eday are the day numbers corresponding to the start and end of the range to be checked, and \$i is the day number being counted (I have it in a 0-6 loop). I moved \$wks outside the function, as there's no point recalculating it each time.

``````\$wks = floor((\$endstamp - \$startstamp)/7*24*60*60);
\$numDays = numDays(\$sday, \$eday, \$i, \$wks);
``````

Make sure the start/end timestamps you're comparing have the same timezone adjustment, if any, otherwise you'll always be off a bit with \$cnt and \$wks. (I ran into that when counting from an unadjusted first of the year to an adjusted day/time X.)

This question is just crying out for an updated answer that uses PHP's DateTime classes, so here it is:-

``````/**
* @param String \$dayName eg 'Mon', 'Tue' etc
* @param DateTimeInterface \$start
* @param DateTimeInterface \$end
* @return int
*/
function countDaysByName(\$dayName, \DateTimeInterface \$start, \DateTimeInterface \$end)
{
\$count = 0;
\$interval = new \DateInterval('P1D');
\$period = new \DatePeriod(\$start, \$interval, \$end);

foreach(\$period as \$day){
if(\$day->format('D') === ucfirst(substr(\$dayName, 0, 3))){
\$count ++;
}
}
return \$count;
}
``````

## To count The Total Friday Between Two Dates##

``````\$from_date=(2015-01-01);

\$to_date=(2015-01-20);

while(strtotime(\$from_date) <= strtotime(\$to_date)){

//5 for count Friday, 6 for Saturday , 7 for Sunday

if(date("N",strtotime(\$from_date))==5){
\$counter++;
}
\$from_date = date ("Y-m-d", strtotime("+1 day", strtotime(\$from_date)));

}

echo \$counter;
``````