Video frame rate calculator?

[-Tragedy-]

Hey all,

Do any of you know of a video frame rate calculator (Win7 or online) which allows be to add and subtract times?
I'm sick of doing it on paper... Eats up too much of my time.

Cheers.

[Psychotime]

...Huh? I have no idea what you're asking for.

Add and subtract times of what?

I see you're an animation student, but I'm still lost on what on earth you're talking about that would require some special calculator.

[-Tragedy-]

Ah.. Good point.... Probably was a bit difficult to understand...

I'm after a calculator, be it physical or software/website that allows me to add and subtract video time-code.
For example:

This is a time-code for video.

hh:mm:ss:ff

(hours:minutes:seconds:frames)

eg:
00:01:07:24
-00:00:52:07
=??:??:??:??

I can do it with pen and paper and in my head, however it would be much simpler to just punch in some digits into a calculator of sorts.
I've done some googling, found some stuff like:
https://www.apple.com/downloads/dash...torwidget.html

However I haven't found one for Windows.

Yeah, I can do it by hand, but I'm lazy and have been up for 23 hours so far with client work; once it gets to those stupid hour days the last thing I want to do is number-crunch...
Just want to get the work done.

Simply put, the human thought process of "there must be a simpler way!".

Cheers.