The Apple Watch’s Resting Calorie Calculations Are Still Way Off

The Apple Watch has been out for several months now, and one of the issues that has been apparent from the beginning still hasn’t been fixed. As I noted shortly after I got my Apple Watch, the resting calories calculation is way off.

It’s actually not the watch that calculates this; it’s the Activity app that collates data from the watch and makes calculations. (You can only see active calories on the Apple Watch.)

Here’s an example from the other day. I walked 7,678 steps, for a distance of 4.1 miles. (And, yes, I’ve told the Apple Watch to display kilometers, not miles, but that’s not fixed either…)


And for this much activity, the Activity app tells me I have burned a total of 4,090 calories.


This is, of course, ludicrous. As I point out in this article, no calorie calculator gives numbers anywhere near the 3,274 resting calories the Apple Watch calculates. At most, my resting calories should be around 2,000.

This isn’t a fix that needs to be made to the Apple Watch’s software; this should be fixed in the Activity app. It’s surprising that Apple hasn’t fixed this; it seems trivial to see that the algorithm is wrong, and to fix it. There are plenty of threads on Apple’s forums discussing this, and their own testing should have shown that this is a problem.

Interestingly, a post on Reddit says “Apple seem to have got the Resting Calories more accurate […] This is on WatchOS 2 beta 3.” It doesn’t make sense that this is calculated on the watch, since it is a more or less fixed number (it should change slightly as your weight changes). But I think it’s very poor of Apple to have been providing this incorrect data for so long. When WatchOS 2 is released, many people will have had their watches for 5 months.