Where to find battery health on your iPhone
Open Settings, then tap Battery, then Battery Health & Charging. You will see a percentage labeled Maximum Capacity — this is your battery health. It shows what percentage of the battery's original charge capacity remains.
This screen also displays Charging Optimization status and Battery Condition, which tells you whether the battery is functioning normally or needs service. If Battery Condition shows anything other than "Normal", the battery may be degraded or damaged.
The Battery Health & Charging screen is available on iPhone XS and newer. If you have an older model, you can still see battery status in Settings > Battery, but the detailed health percentage will not appear.
Key Takeaways
- Maximum Capacity percentage in Settings > Battery > Battery Health & Charging shows how much of your battery's original charge capacity remains.
- A battery at 80% capacity or higher is considered healthy; below 80% means the battery is aging and may need replacement sooner.
- Battery Condition status tells you whether Apple detected any problems — "Normal" means the battery is working as expected.
- Older iPhones show less detail, but you can still monitor battery drain patterns in Settings > Battery > Battery Usage to spot problems early.
What the percentage actually means
Maximum Capacity measures how much charge your battery can hold compared to when it was new. A reading of 100% means the battery is brand new or has been replaced. A reading of 85% means the battery can now hold 85% of the charge it originally could.
All lithium batteries lose capacity over time through normal use. Apple considers 80% capacity the threshold where a battery is no longer at peak performance. Most iPhone batteries are designed to retain 80% capacity after 500 full charge cycles — roughly two years of typical use.
The percentage does not tell you how long your phone will last on a single charge today. That depends on how much you use it. A phone with 70% battery health will still run all day if you use it lightly, but may need charging by afternoon if you use it heavily.
What Battery Condition status means
Normal means the battery is functioning as expected and does not need service. This is the status you want to see.
Service Recommended means Apple detected that the battery is not holding a charge as well as it should, but the phone is still usable. You can continue using your iPhone, but you may notice the battery drains faster or the phone shuts down unexpectedly at low battery percentages. Battery replacement is available through Apple or an authorized repair shop.
Service Battery (on some models) or Battery Degraded means the battery has degraded significantly and Apple recommends replacement. The phone may shut down suddenly even when the battery percentage shows charge remaining.
How to read Charging Optimization
Charging Optimization is a separate feature from battery health. When it is on, your iPhone learns your charging patterns and slows charging to 80% until you need the phone, then finishes the charge. This reduces the time the battery spends at 100%, which slows capacity loss.
You can turn Charging Optimization on or off in the same Battery Health & Charging screen. Turning it off means your phone will charge to 100% as soon as possible, which will degrade the battery faster over time.
Why your battery health dropped quickly
If your Maximum Capacity dropped more than 10% in a few months, something is wearing the battery faster than normal. Common causes are heavy use (gaming, video streaming, or constant background activity), exposure to heat, or a defective battery.
Check Settings > Battery > Battery Usage to see which apps are draining the most power. If one app is using far more than others, try closing it when you are not using it or uninstalling it. If battery health continues to drop rapidly and Battery Condition shows Normal, the battery itself may be defective — contact Apple Support to discuss replacement options.
Heat is the biggest enemy of battery health. Avoid leaving your iPhone in direct sunlight, in a hot car, or in a case while charging. If your phone feels warm during normal use, it is working harder than it should and the battery is aging faster.
When to replace your battery
You do not have to replace the battery the moment it drops below 80%. Many people use iPhones with 70% or 60% capacity without problems. Replace the battery when one of these things happens: Battery Condition shows Service Recommended or worse, the phone shuts down unexpectedly at low battery percentages, or the battery drains so fast that you cannot use the phone for a full day on a single charge.
Battery replacement through Apple costs between $50 and $100 depending on the model. Third-party repair shops often charge less, but quality varies. If your iPhone is still under warranty or covered by AppleCare+, battery replacement may be covered.
Frequently Asked Questions
Is 80% battery health bad?
No. Eighty percent is the point where Apple considers the battery no longer at peak performance, but it is still healthy and normal. Most people do not notice a difference in daily use at 80% versus 100%. Replace the battery when it drops below 80% only if you are experiencing problems like unexpected shutdowns or severe drain.
Can I improve my battery health percentage?
No. The Maximum Capacity percentage reflects permanent chemical changes in the battery and cannot be reversed. You can slow future degradation by keeping the phone cool, using Charging Optimization, and avoiding full discharge cycles, but you cannot restore capacity that has already been lost.
Why does my battery health show a different percentage than yesterday?
The percentage can fluctuate slightly day to day based on temperature, charging patterns, and how the battery is being used. Small changes of 1 to 2% are normal. If it drops 5% or more in a single day, the battery may be defective or your phone is overheating.
Does closing apps or restarting my phone improve battery health?
No. Closing apps and restarting do not change the Maximum Capacity percentage. Those actions may improve battery drain in the short term, but they do not repair or restore the battery itself. Battery health is a measure of chemical capacity, not software performance.
What if Battery Condition says Normal but my phone still drains fast?
Fast drain with Normal battery health usually means an app is using too much power, your screen brightness is high, or background activity is heavy. Check Settings > Battery > Battery Usage to find the culprit. If battery health is above 80% and Battery Condition is Normal, the battery itself is fine — the drain is a software or usage issue.