Every iPhone shows a battery health percentage under Settings → Battery → Battery Health & Charging. It is one of the most useful numbers on your phone — here is what it actually means.
What the percentage means
Battery health compares your battery's current maximum capacity to when it was new. At 100%, a full charge holds as much power as the day you bought it. At 80%, a "full" battery genuinely holds a fifth less — which is why an older phone needs charging by mid-afternoon when it used to last all day.
Signs your battery is worn
- Battery health at or below about 80%
- The phone dies suddenly, even showing 20–30% remaining
- Noticeably faster draining than it used to
- The phone slows down — iOS can deliberately reduce performance to protect a worn battery ("peak performance capability" messages)
- A message that the battery "may need to be serviced"
What a battery replacement actually fixes
A new battery restores full capacity and removes any performance throttling — for many phones it genuinely feels like a new device, at a fraction of the cost of replacing the phone. It will not fix faults unrelated to the battery, which is why we test your device and confirm everything with you before any work begins.
Worth doing? Usually, yes
If your phone is otherwise healthy and you are happy with it, a battery replacement is one of the most cost-effective repairs there is. Find your model in our repair services — batteries are usually fitted in store the same day, with a 12-month warranty on parts and labour.
