Question: I see there are other posts on this question in other languages, but I can't find one for PHP. I'm not looking for the difference between two date times, but rather how many days different. For example:

`2011-08-06 14:05:28`

and

`2011-08-07 08:46:28`

are less then one day apart, but I want a function that will tell me they are on days that are one day apart, i.e. will return a value of `1` for these two dates, and return a value of `2` for the following dates, for example:

`2011-08-06 23:05:28`

and

`2011-08-08 01:46:28`

Really, I'm guessing it must be easy, but I've not worked much with dates before.

Oh, and one more constraint, I need something compatible with PHP 5.2, so can't use `DateTime::diff`.

EDIT: changed to clarify that I do really need a numeric return value, sorry :)

Answer: 
```
$date1 = "2011-08-06 14:05:28";
$date2 = "2011-08-07 08:46:28";
if(date('Ymd', strtotime($date1)) == date('Ymd', strtotime($date2)))
{
    // Same day!
}

```

**Update**

If you really want the number of days between to dates, I suggest you update to PHP 5.3. Calculating the number of days can be rather difficult, especially if you want to be able to handle days in different years.

```
$days = abs(date('z', strtotime($date1)) - date('z', strtotime($date2)));

```

This is the best I can do, but it *requires* that `$date1` and `$date2` are in the same year.
I would try something like this (using mainly timestamps):

```
/**
 * @param string $date1
 * @param string $date2
 * @return int
 *   Number of days between the two dates.
 */
function date_diff_days($date1, $date2) {

    // Ignore the time part and convert the date part to timestamp.
    $date1 = substr($date1, 0, 10);
    $date1 = strtotime($date1 . ' 00:00:00');
    $date2 = substr($date2, 0, 10);
    $date2 = strtotime($date2 . ' 00:00:00');

    // Compute the difference in seconds.
    $diff_secs = abs($date1 - $date2);

    // Convert the difference to days.
    $diff_days = ceil($diff_secs / (60 * 60 * 24));

    return $diff_days;

}

```

I tried it out with both your test cases and it worked just as you wanted. If you want any changes, you can edit the function. Hope it helps!