What does your Body Battery number mean?
Body Insights reads supported Apple Health records and shows a 0 to 100 Body Battery reserve. You can see it on iPhone and Apple Watch. Carry-over and sleep build the starting reserve. Energy use during the day lowers the current reserve.
Your current reserve is the energy left for the day. A higher number leaves more room for a demanding task. If the number is low, compare it with how you feel before you add another demand.
What does the Body Battery card show?
The iPhone card shows how the current reading relates to your starting reserve. It lists carry-over and points added by sleep, then shows the reserve left now. Apple Watch keeps the current percentage and trend easy to check.
Current reserve
iPhone and Apple WatchThe 0 to 100 reserve left now
Carry-over
iPhoneReserve carried forward from the previous cycle
Sleep added
iPhonePoints restored from your latest available Sleep Score
Starting reserve
iPhoneYour reserve after carry-over and sleep recharge
How can you use Body Battery?
Check your current reserve before the next demanding part of the day. Use the number with how you feel and what is still ahead. It does not overrule how you feel.
Use it before the next demand
If you have a demanding afternoon and your reserve is lower than expected, make one task smaller or move it. If the number is high but you still feel unwell, trust how you feel rather than the score.
Example: A 60% current reserve
A 60% current reserve means the app shows 60 points left now. Open the iPhone card to see the carry-over, points added by sleep, and starting reserve behind it. Compare that 60% with how you feel before you decide what else fits into the day.
Why can iPhone and Apple Watch differ?
iPhone and Apple Watch can refresh at different times as new Apple Health records arrive. This can leave the two views with different current readings for part of the day.
iPhone
- View
- Current reserve with recharge breakdown
- Context
- Carry-over, sleep added, starting reserve, and current reserve
- Best use
- See what built the starting reserve and what remains
Apple Watch
- View
- Current reserve with daily trend
- Context
- Status, data source, and last update time
- Best use
- Check the current reserve without opening your iPhone
If the numbers differ, check the last update and open the iPhone card for the full recharge breakdown.
What happens when data is missing?
Body Insights can estimate the reserve from steps when some energy data is missing. The card will ask you to sync Apple Watch for a more accurate reading. If today's energy data is unavailable, the iPhone card may show your last saved Body Battery reading. A notice explains that this is not today's reading. If there is no usable current or saved reading, the card shows No Data.
Check your Body Battery
See your current 0 to 100 reserve on iPhone and Apple Watch.
See my Body Battery