Time sheet help in pdf

As correctly mentioned by @ls_rbls , such calculations are not trivial.

If you're interested, I've developed a (paid-for) tool for Acrobat that allows you to set them up quite easily and quickly, and without having to write any code. You can find it here:

https://www.try67.com/tool/acrobat-calculate-time-differences-in-a-worksheet

You can't calculate the difference in hours between two given times using simplified field notation in Acrobat like that.

For instance, you are using a 24 hour clock format in your fields (also known as military time), in which case,  you've formatted the fields to use hours and minutes  expressed as "HH:MM"; then in the total hours fields you've formatted those fields to Numbers with two decimals.

When you work with a 24 hour clock you need to keep in mind the appropriate conversions between seconds and minutes, and how to substract them or add them accordingly when time is at noo or 1200 hundred hours, and when time is at 2400 hours (or midnight).

The link below describes in detail the appropriate explanation on how and why to use military time, and how you get the total difference in hours given two different times:

• https://smallbusiness.chron.com/calculate-average-hours-work-per-employee-15998.html

Ande when it comes to trying to achieve this with Acrobat JavaScript, please take a look at the script provided by ACP Thom Parker in the following thread:

• https://answers.acrobatusers.com/How-I-Calculate-Hours-Between-Two-Dates-Times-q74426.aspx

The Adobe Acrobat's built-in features obviously does not address this type of calculation so would need to employ JavaScript scripting and test your formula until your calculations are accurate.

Just remember, to differintiate between am or pm 12 hour clock format versus using military time, hours and minutes are expressed without the column in between hours and the minutes":".