I would greatly appreciate having the formula you have developed for people! Thank you!Flynn,
1. Convert Mia's desired weight from pounds to kilograms. I want to keep Mojo at 16.5, so: 16.5 pounds X .454 = 7.48 kilograms
2. Plug the desired kilograms into this formula: (30 X 7.48) + 70 = 294 calories to meet basal metabolic functions.
3. Now you factor in your dog's activity level. I used "light" (but not couch potato) which is a 1.1. So take the calories you got in step 2 and multiply it by the 1.1. 294 X 1.1 = 324. That's what he can have on an average day. If we walk a lot or work on a lot of physical training, he can have a little more. If I get lazy and he doesn't get a daily walk, he gets a little less.
This formula is one of several I've found. It has worked for Mojo (he holds the desired weight and never appears to be hungry). I use it in conjunction with how he "feels" under my hands. But it won't work for all dogs. Age, environment (temps under 50 F and over 86 F), breed, health of the dog, pregnancy, lactation, and activity duration and intensity will all come into play. I've seen activity factors that range from 1.1 to 1.95 (check out Small Dogs Paradise if you want a nice breakdown on those).
Dog food bags will give you the calorie count per cup (at least those that I have used do). But they seem to really, really overestimate how many calories a day the average, nonworking dog needs.
I'll PM you how to calculate for people. It's more complicated, but I'll put together a worksheet that you can just plug numbers into!