Battery and charging
Battery Health
Most people call this how worn out your battery is.
This screen shows what percentage of its original capacity your battery still holds, and warns you when it has aged enough to affect the phone.
This setting is present on your iPhone.
- We have this path on file but have not yet confirmed it against an official source.
Where to find it - iOS 18 and later
- Settings
- Battery
- Battery Health
What it does
Maximum Capacity compares your battery now against a new one. A number near 100 percent means little wear. As it falls, the phone runs for less time on a charge.
The same screen reports Peak Performance Capability, which tells you whether the battery can still deliver power quickly enough under load.
What changes
When it is on
Nothing changes. This is information, not a switch.
When it is off
Not applicable.
Should you turn it on?
Battery
No real change
Privacy
No real change
Performance
No real change
Cellular data
No real change
Storage
No real change
Out of the box: Always available. The number updates over time rather than instantly.
Where this setting used to live
Apple moves settings between releases. This is every location we have on file.
-
iOS 18 and later
Settings > Battery > Battery Health
-
iOS 16 to iOS 17
Settings > Battery > Battery Health & Charging
-
iOS 11 to iOS 15
Settings > Battery > Battery Health
Questions people actually ask
- What battery health percentage is bad?
- Under about 80 percent you will notice shorter days, and Apple treats that point as the end of the battery's rated life.
- Can I improve battery health?
- No. Capacity only goes down. You can slow the decline with charge limits and by avoiding heat, but you cannot recover lost capacity.
If it is not working
- A newly restored or newly replaced battery can report an odd number for the first few charge cycles.
- Below roughly 80 percent capacity, Apple treats the battery as consumed and a replacement is the real fix.
- A message about an unknown part means the battery was replaced with one the phone cannot verify.