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: 
if i interpret the question correctly, you need [GregorianToJD](http://php.net/manual/en/function.gregoriantojd.php) or mysql [to\_days](http://dev.mysql.com/doc/refman/5.6/en/date-and-time-functions.html#function_to-days)

Both functions return a [julian day](http://en.wikipedia.org/wiki/Julian_day) for a specific date, which is basically the number of days since "day 0".
```
$secondsApart = strtotime( '2011-08-07 08:46:28' ) -
                   strtotime( '2011-08-06 14:05:28' );

```

Now you can compute any other value based on that:

```
$hoursApart = round( $secondsApart / 3600 );
$daysApart = round( $secondsApart / 86400 );
...

```

You can also use floor() or ceil() instead round() if that better suits your need.