I am measuring my food at home and having questions how to calculate your own food that you prepare. Example: I made chicken salad and want to calulate all calories used. Is there a formula for this type of thing?

The only way I know of is to use math (damn, I actually have to use that crap from school :-). Take ingredients. Find out how much of a serving you used when you added it to the recipe, multiply that times the calories/macros from the label, repeat for each ingredient. Keep line items seperate. You can always tweak the recipe by modifying the incredient amounts... more chicken = more protein!

When you have made the recipe, if you eat half of it, divide the total calories/macros by 2.

Add a spreadsheet, and imagine what you can do! I will leave that as an excersize for the reader!