Battery health explained: what 87% actually means
The number in Settings is not the whole story. Here is how to read it, and how to keep it high.
GadgetDeals KE · 2 Dec 2025 · 5 min read
Battery health is a percentage comparing your battery's current maximum capacity to what it held when it left the factory. At 87%, a phone that once ran 10 hours will run roughly 8 hours 45 minutes — assuming the same usage.
Why we test rather than read The software figure is an estimate that drifts, and it can be reset by third-party tools. Every phone we sell is discharged under a controlled load and measured, so the figure we publish reflects real capacity rather than what the phone claims about itself.
Charge cycles matter too One cycle is a full 0-100% worth of charge, however it accumulates. We publish cycle counts alongside health because a phone at 90% with 200 cycles will age more gracefully than one at 90% with 900.
How to keep yours healthy Keep the phone between 20% and 80% where you can. Heat is the real enemy — never charge under a pillow or leave the phone on a car dashboard. Use a charger rated for your phone; cheap unregulated chargers cause more long-term damage than fast charging ever will. Enable Optimised Battery Charging so the phone finishes the last 20% just before you wake up.
When to replace Below 80%, replacement is usually worth it. A battery replacement at our repair centre costs a fraction of a new phone and restores full runtime. Every phone we sell that tests below 85% gets a new battery before it is listed, not after you complain.
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