Where can a calculator for calories be found?

There are many online calculators and offline software solutions for calculating nutritional information.

I recommend an online service as the results you create will always be where you are working so long as you are connected to the web.

Our company uses alacalc.com because they're quick and easy to use, provide a GDA graphic and do things like vitamins and iron calculations.

They calculate allergens too, I've not seen any others that do the allergens for you.