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How Many Days Since a Date and other Calculations
Here i calculate the number of days since a certain date in php and use the values for checking how much something costs per day.
Lets add the date that the item was purchaced. In date format Year-Month-Day
$date_start = date_create("2017-10-29");
Get todays date according to the server date with php
$todays_date = date_create(date('Y-m-d'));
Check the difference between the dates
Using the date_diff function we can check the difference between these dates.
$diff = date_diff($date_start,$todays_date);
Output the details
I usually like to add all the data into a variable and then return it so here we will add all the data to the variable $template_result. This will give us the amount of days since the original date.
$template_result = 'Number of Days Since 29th October 2017 is '.$diff->format("%a");
Using this number we can calculate different things like how many years or months since a date.
Years Since Calculation
Calculate the Years since the date.
$years_calc = $diff->format("%a") / 365;
$years_calc = number_format($years_calc, 2);
$template_result .= "<p>Years $years_calc </p>";
Cost per Day
If the item has an original value we can then calculate the cost per day using the original number.
$cost = 331;
$per_day = $cost / $diff->format("%a");
$per_day = number_format($per_day, 2);
$template_result .= "<p>Original Total Cost: $$cost, Cost per Day $$per_day </p>";
Return the results
Now we can just return the results or just echo them.
You can see a working demo below.
DemoNumber of Days Since 29th October 2017 is 543
Original Total Cost: $331, Cost per Day $0.61