Can’t find the answer you’re looking for? Reach out to our customer support team.
About the problem
Why are my Apple Watch calories randomly lower some days?
Most likely, your Apple Watch failed to estimate resting calories for some hours — usually overnight while it was charging. This is a known issue that started with watchOS 10 and is still present in the latest version, affecting all Apple Watch models. It doesn’t happen every night, which makes it hard to diagnose. If you’re tracking calories for weight loss using apps like Lose It! and other calorie trackers, these gaps can significantly throw off your daily calorie budget — making it look like you burned far less than you actually did.
I’ve tried restarting and re-pairing my Apple Watch. Will that fix it?
Unfortunately, restarting or re-pairing your Apple Watch only fixes the issue temporarily, if at all. The problem tends to come back within days.
About the app
What is Calorie Gap and why do I need it?
Calorie Gap detects missing resting energy (basal calorie) data in Apple Health. Devices like Apple Watch sometimes fail to record every hour — especially overnight while charging — leaving gaps that throw off your daily burn. Calorie Gap finds those gaps, estimates the missing calories, and writes them to Health so your daily burn is accurate.
How does the app estimate missing calories?
It looks at your recent resting energy burn rates — particularly the hour just before a gap — and uses that as the basis for an estimate. During sleep hours it can use a lower sleep burn rate instead. You can fine-tune the estimation behaviour in Settings.
Is my health data shared or stored on a server?
No. All processing happens entirely on your device. Calorie Gap reads and writes data through Apple Health and never sends your health information to any external server.
What does the free trial include?
The 14-day free trial gives you full access to every feature, including gap detection, automatic and manual gap filling, and notifications. After the trial you can unlock permanent access with a one-time purchase.
Can I undo a gap fill?
Yes. Tap on any filled gap in the timeline to see its details, then use the undo action to remove the data that was written to Health. The gap will reappear so you can re-fill it if needed.
What Health permissions does the app need?
Calorie Gap needs read and write access to Resting Energy in Apple Health — read to detect gaps and write to fill them. It also asks for optional read access to Dietary Energy. This isn’t used for calorie calculations, but it lets the app wake up in the background when you log food, which makes automatic gap filling and notifications more reliable. Health data is normally inaccessible while your device is locked, so this extra trigger helps the app catch gaps sooner. You can manage all permissions in the Health app under Data Access & Devices.
