The iPhone battery health percentage shows the estimated maximum capacity of the cell, and it is the first signal that a battery is ageing. A reading above 80 percent means the cell is still usable, while a reading below 80 percent means a replacement is the honest recommendation. Digi4u stocks tested iPhone batteries.
Last updated: August 2026 ¡¤ Reviewed by the Digi4u repair team.
About this guide: based on in-house bench testing and repair experience; confirm model specifications and grades with the supplier before ordering.
Where to find the battery health screen
Open Settings, then Battery, then Battery Health and Charging. The screen shows the maximum capacity as a percentage and the peak performance capability of the phone.
The health percentage is an estimate based on charge cycles and voltage patterns, so treat it as a signal rather than a precise measurement. Battery reporting and health indicators vary by device, software version and replacement part.
What the percentage means
A reading above 80 percent means the cell still holds most of its original capacity and is usable for everyday use. A reading below 80 percent means the cell has aged past its useful capacity.
| Health reading | What it means |
|---|---|
| 90¨C100% | Cell is healthy |
| 80¨C90% | Cell is ageing but usable |
| Below 80% | Replacement is recommended |
The reading is the first signal, and a charging log confirms the pattern.
The other signals
The health percentage is not the only signal: shutdowns above 20 percent, swelling, and a sudden drop in health all point to a worn cell. A charging log reveals whether the drain is consistent.
The battery draining guide covers the diagnosis, and the swollen battery guide covers the safety case.
When to replace
Replace the battery when the health drops below 80 percent (a common reference point), the phone shuts down early, or the battery swells. The replacement should match the model’s connector and grade.
The iPhone battery replacement guide covers the full bench process.
The health percentage is an estimate, not a measurement, and the charging log is the confirmation. Explaining this avoids the dispute that follows a surprising reading.
Set expectations with the customer: above 80 percent is usable, below 80 percent is aged, and the drain pattern decides the timing.
Record the model, the health reading, the log and the grade so the recommendation can be reviewed if the customer questions it.
The health percentage is an estimate, not a measurement, and the charging log is the confirmation. The explanation is part of the service.
The health screen also tells the shop which advice to give: a customer above 80 percent needs the lifespan tips, and a customer below 80 percent needs the replacement workflow from the iPhone battery guide.
Sources: Apple support documentation on iPhone battery health; last reviewed August 2026. The health percentage is an estimate and varies by device and usage.
Battery health across iPhone generations
iPhone XS and later, including the SE 2nd and 3rd generations, show battery health in Settings, and newer iPhones also display cycle count there (iPhone 15 and later). The original iPhone X shows maximum capacity and peak performance capability without the parts-pairing behaviour of the later models, while a non-genuine battery can hide the percentage on the paired models.
Digi4u workshop notes
The health percentage is the first signal, but the charging log is the evidence. Use both before recommending a replacement.
¡ª Digi4u repair team (bench notes)
Conclusion
The battery health screen is the first signal that a cell is ageing, and a reading below 80 percent makes a replacement the honest recommendation. Confirm with a charging log and match the cell to the model. Repair shops can offer the health check with every screen repair and stock tested iPhone batteries at Digi4u.
Frequently Asked Questions
Where is the battery health screen on an iPhone?
Open Settings, then Battery, then Battery Health and Charging.
Is 82 percent battery health bad?
No. Health above 80 percent is still usable; monitor the charging log before deciding on a replacement.
Can the battery health percentage be wrong?
The percentage is an estimate based on charge cycles and voltage patterns, so treat it as a signal rather than a precise measurement.
