Where to find your iPhone's battery health information

Your iPhone stores a battery health report that you can read in Settings. Open Settings, then go to Battery, then Battery Health & Charging. You will see a percentage labeled Maximum Capacity — this is the number that matters most. It tells you how much charge your battery can hold right now compared to when it was brand new.

This screen also shows Cycle Count on some iPhone models (iPhone 16 and newer), which counts how many times you have fully charged and drained the battery. A higher cycle count means the battery has been through more charge cycles, which naturally reduces its ability to hold a charge over time.

If you have an older iPhone model, you may not see cycle count — Apple added this detail only recently. The maximum capacity percentage is available on all iPhones running iOS 16 or later, so make sure your phone is up to date before looking for this information.

Key Takeaways

  • Maximum Capacity in Settings shows what percentage of the original charge your battery can now hold, and anything above 80 percent is considered healthy.
  • Cycle Count (on newer iPhones) tracks how many full charge cycles your battery has completed, with higher numbers indicating more wear.
  • A battery at 80 percent capacity or below may trigger Performance Management, which slows your phone to prevent unexpected shutdowns.
  • Battery health naturally declines over time and use — this is normal chemistry, not a defect, and does not mean your phone is broken.
  • You can request a battery replacement from Apple if your maximum capacity has dropped below 80 percent and your phone is still under warranty or covered by AppleCare+.

What maximum capacity percentage actually means

Maximum Capacity is not the same as your current battery level. If your maximum capacity shows 85 percent, it means your battery can now hold 85 percent of the charge it held when new. If you charge it to 100 percent today, you are actually charging it to 85 percent of its original capacity. Over time, this number will drop — that is the normal wear pattern for all rechargeable batteries.

Apple considers a battery healthy if it retains 80 percent or more of its original capacity. Most iPhones reach this threshold after two to three years of normal use. If your maximum capacity drops below 80 percent, your phone may start using Performance Management, which reduces processing speed to prevent the phone from shutting down unexpectedly when the battery cannot deliver enough power.

The decline is not linear. Your battery may drop from 100 percent to 90 percent over the first year, then from 90 percent to 80 percent over the next year. After that, the decline often slows. This variation depends on how you charge, how often you use the phone, and the temperature where you keep it.

How cycle count relates to battery wear

A cycle is one complete charge from empty to full, or the equivalent spread across multiple charging sessions. If you charge your phone from 50 percent to 100 percent, that counts as half a cycle. If you do that twice in one day, that is one full cycle. Cycle Count on newer iPhones shows the total number of complete cycles your battery has completed since it left the factory.

Batteries are rated for a certain number of cycles before they degrade noticeably. Most modern iPhone batteries are rated for around 500 cycles before they drop to 80 percent capacity. If your phone shows 300 cycles and 85 percent capacity, your battery is wearing at a normal pace. If it shows 200 cycles and 60 percent capacity, something is causing faster-than-normal wear — usually heat exposure or a defective battery.

Cycle count alone does not tell you whether your battery is healthy. A phone with 400 cycles and 82 percent capacity is in better shape than a phone with 200 cycles and 75 percent capacity. Always look at the maximum capacity percentage first, then use cycle count to understand whether the wear is happening at a normal rate.

Why your battery health declines over time

Battery degradation is chemistry, not a design flaw. Lithium-ion batteries (the type in iPhones) lose capacity every time they charge and discharge. Electrons move through the battery's internal structure, and over thousands of cycles, the materials that carry those electrons wear down. This happens to every rechargeable battery — phones, laptops, electric cars, and power tools all follow the same pattern.

Heat accelerates this wear significantly. If you regularly charge your phone in a hot car, use it while it is charging, or keep it in direct sunlight, the battery will degrade faster than normal. Cold temperatures slow down the chemical reactions inside the battery temporarily, which is why your phone may show lower battery percentage in winter, but the battery itself is not damaged.

How you charge also matters. Keeping your phone plugged in overnight after it reaches 100 percent, or regularly draining it completely to zero, both cause faster wear than charging to 80 percent and unplugging. If you want to slow battery degradation, avoid heat, avoid letting the battery sit at 100 percent for long periods, and avoid letting it drop below 20 percent regularly.

When to consider a battery replacement

If your maximum capacity is 80 percent or higher, your battery is still within Apple's definition of healthy and you do not need to replace it. The phone will work normally and Performance Management will not set up. If you notice your phone shutting down unexpectedly or running slowly, check the battery health first — if it is above 80 percent, the problem is something else.

If your maximum capacity has dropped below 80 percent, you have options. If your iPhone is still under the one-year limited warranty or covered by AppleCare+, Apple will replace the battery for free or a small fee. If your warranty has expired and you do not have AppleCare+, Apple charges a flat fee (usually $69 to $99 depending on the model) for an out-of-warranty battery replacement. Third-party repair shops often charge less, but using non-Apple parts may affect water resistance and other features.

You do not have to replace the battery when ready once it drops below 80 percent. If the phone still holds a charge long enough for your day and you do not mind Performance Management slowing it down slightly, you can wait. But if you plan to keep the phone for another year or two, replacing the battery now will make it feel faster and more responsive.

How to slow battery degradation going forward

The most important step is keeping your phone cool. Avoid leaving it in hot cars, direct sunlight, or in a case while charging if the phone gets warm. If your phone feels hot to the touch during charging, unplug it and let it cool down before continuing.

Enable Optimized Battery Charging in the same Battery Health & Charging settings screen. This feature learns your charging patterns and holds your battery at 80 percent until shortly before you usually wake up or use your phone, then charges to 100 percent. This reduces the time your battery spends at full charge, which slows degradation. The tradeoff is that your phone may not be at 100 percent when you first pick it up in the morning, but the battery will last longer overall.

Charge more often and to lower levels rather than waiting until the battery is nearly dead. Charging from 20 percent to 80 percent causes less wear than charging from 5 percent to 100 percent. If you use your phone heavily, consider charging it twice a day rather than once. Smaller, more frequent charges are gentler on the battery than one large charge.

Reading your battery health report accurately

The Battery Health & Charging screen shows only current information — it does not show a history of how your battery has degraded over time. If you want to track changes, take a screenshot of the maximum capacity percentage and note the date. Check it again in three months or six months to see whether the decline is happening at a normal pace or faster than expected.

Do not compare your battery health to someone else's phone. A two-year-old iPhone with 82 percent capacity is normal. A six-month-old iPhone with 92 percent capacity is also normal. The rate of decline varies based on usage patterns, climate, and charging habits. What matters is whether your own phone's health is declining at a steady, predictable rate or dropping suddenly, which could indicate a defective battery.

If your battery health drops 10 percent in a single month, or if your phone shuts down unexpectedly even though the battery percentage shows 30 percent or higher, contact Apple. These are signs of a defective battery, not normal wear, and Apple will replace it under warranty even if the maximum capacity is still above 80 percent.

Frequently Asked Questions

Is 85 percent battery health good?

Yes. Apple considers any battery at 80 percent capacity or higher to be healthy. At 85 percent, your battery is well within normal range and will not trigger Performance Management. Most iPhones reach this point after one to two years of regular use.

What does it mean if my iPhone shows Performance Management enabled?

It means your battery maximum capacity has dropped below 80 percent and your phone is running slower to prevent unexpected shutdowns. You can turn off Performance Management in Battery Health settings, but your phone may shut down without warning if the battery cannot deliver enough power. Replacing the battery will restore full speed.

Can I check my battery health without going into Settings?

Not directly from the home screen. You must go to Settings > Battery > Battery Health & Charging. Some third-party apps claim to show battery information, but they cannot access the same detailed data that Apple's own settings display, so the numbers may not match.

Why is my battery health already low after just a few months?

Rapid battery degradation usually comes from heat exposure, frequent full discharges, or leaving the phone plugged in at 100 percent for long periods. Check whether you are charging in a hot environment or using the phone while it charges. If the phone is brand new and the battery is already below 90 percent, contact Apple — this may indicate a defective battery.

Does checking my battery health drain the battery?

No. Opening the Battery Health & Charging screen uses almost no power and will not affect your battery's lifespan or current charge level.