How to use this tool
- 1Enter the factory battery capacity (mAh) from the phone's spec sheet.
- 2Enter the current capacity, from battery apps or ADB (dumpsys battery).
- 3See the health percentage and the verdict.
About this test
Battery health is the ratio between the capacity the battery still holds and its original factory capacity. Charge cycles gradually reduce that capacity and your battery life with it.
A battery at 80% health or more is still considered good. Below that, unexpected shutdowns, short battery life and sudden percentage drops become common, signs a replacement is due.
Privacy: this tool runs entirely in your browser. No image, audio or device data is recorded or sent to any server.
Frequently asked questions
How do I find the current battery capacity?
Use battery diagnostic apps or the ADB command 'dumpsys battery'. Some manufacturers show battery health right in settings.
At what percentage should I replace the battery?
There's no fixed rule, but below 80% health the experience usually degrades a lot. If the phone shuts down with charge remaining, consider replacing.