Where to find your iPhone battery health right now

Open Settings, then tap Battery, then Battery Health & Charging. You will see a percentage labeled Maximum Capacity — that is your battery health. It tells you what fraction of the battery's original charge it can still hold.

If you see Battery Health Management turned on below that percentage, your phone is intentionally slowing down charging to extend the battery's lifespan. This is normal and happens automatically on iPhones running iOS 13 or later.

The same screen shows Charging Voltage and Peak Performance Capability if your battery has degraded enough to affect how fast your phone runs. Most people never see those warnings — they appear only when the battery is significantly worn.

Key Takeaways

  • Maximum Capacity shows what percentage of the original charge your battery can hold, found in Settings > Battery > Battery Health & Charging.
  • A battery at 80% capacity is considered normal wear after a year or two of daily use and does not require replacement.
  • Battery Health Management slows charging speed to reduce wear, and turning it off will degrade the battery faster but charge it quicker.
  • If Maximum Capacity drops below 80% within the first year, your battery may be defective and covered under Apple's one-year warranty.

What the percentage actually means

Maximum Capacity is the amount of charge your battery can store right now, compared to when it was brand new. A phone showing 85% can hold 85% of the charge it held on day one. This is not the same as your current battery level — that is the separate percentage you see in the status bar.

All lithium batteries lose capacity over time. Apple's testing shows that a typical iPhone battery retains about 80% of its capacity after 500 full charge cycles. One charge cycle means draining the battery completely and charging it back to 100%, though it does not have to happen in a single day.

At 80% capacity, your phone still works normally. The battery straightforward holds less total charge, so it drains faster during the day. You might notice you need to charge more often, but performance does not slow down at this point.

When battery health becomes a real problem

Your phone's performance throttles — meaning it runs slower — only when the battery is too degraded to deliver the power the processor needs. This typically happens around 50% capacity or lower, and Apple will notify you when it occurs. You will see a message saying your iPhone has unexpectedly shut down and that performance has been reduced.

If you see that message, you have two choices: replace the battery through Apple, or accept the slower performance. Replacing the battery costs between $50 and $100 depending on your model, and takes about an hour at an Apple Store or authorized repair shop.

If your battery drops below 80% within the first year of ownership, contact Apple. This may indicate a defective battery covered under the one-year limited warranty, and replacement would be free.

How Battery Health Management works and whether to turn it off

Battery Health Management is a feature that limits how much your phone charges overnight and during periods of heavy use. Instead of charging to 100% when ready, it may stop at 80% or 90% and wait until you need the phone to finish charging. This reduces the stress on the battery and slows the rate at which capacity decreases.

You can turn Battery Health Management off in the same screen where you see your capacity percentage. If you turn it off, your phone will charge to 100% every time, but the battery will degrade faster. Most people should leave it on — the trade-off is worth it if you plan to keep your phone for more than two years.

If you turn it off and later want it back on, you can re-enable it the same way. Turning it off does not damage the battery permanently; it just means the battery will age faster going forward.

Why your battery health dropped faster than expected

If your Maximum Capacity is significantly lower than you expected for the age of your phone, a few things could be happening. Frequent exposure to heat — leaving your phone in a hot car, using it while charging, or running demanding apps in warm weather — degrades batteries much faster than normal use. Cold also damages batteries temporarily, though the capacity usually returns once the phone warms up.

Letting your battery drain completely and stay at 0% for extended periods also accelerates wear. If you have not used your phone in weeks and the battery was fully drained, the capacity may have dropped noticeably.

Finally, some older iPhones (iPhone 6, 6s, 7, and some 8 models) had batteries that degraded faster than normal due to a manufacturing issue. If you own one of those models and your battery health is poor, Apple may have offered a discounted replacement in the past, though that program has ended.

Reading the other numbers on the Battery Health screen

Charging Voltage shows the current electrical state of your battery. This number changes constantly and is mainly useful for Apple technicians diagnosing problems. You do not need to monitor it.

Peak Performance Capability tells you whether your phone is running at full speed or has been throttled due to battery degradation. If it says "Normal", your battery is healthy enough to support full performance. If it says "Reduced" or mentions unexpected shutdowns, your battery needs replacement to restore normal speed.

Some iPhones also show Condition with a status like "Normal" or "Service Recommended". "Normal" means the battery is fine. "Service Recommended" means the battery is degraded enough that Apple suggests replacement, though your phone will still work.

How often to check your battery health

You do not need to check battery health regularly. Once or twice a year is enough to notice trends. Checking it every week will not give you useful information because capacity changes very slowly — you might see a 1% drop over several months of normal use.

Check it more often if you are troubleshooting a specific problem, like your phone shutting down unexpectedly or running slowly. If you are considering selling or trading in your phone, checking the battery health beforehand tells you what to expect when the buyer or trade-in service checks it themselves.

Frequently Asked Questions

Is 75% battery health bad?

No. At 75% capacity, your battery is still healthy and your phone will run at full speed. You will notice it drains faster during the day, but this is normal wear after two to three years of use. You do not need to replace it unless you want longer battery life between charges.

Can I improve my battery health percentage?

No. Maximum Capacity only goes down over time; it cannot be restored by software updates, settings changes, or calibration. The only way to raise it is to replace the battery. However, you can slow future degradation by keeping your phone cool, avoiding complete drains, and leaving Battery Health Management on.

Why does my battery health say "Service Recommended" but my phone works fine?

Your phone works fine because the battery still holds enough charge to power it at full speed. "Service Recommended" just means Apple thinks you would benefit from a replacement — it is a suggestion, not a warning. You can wait until the battery degrades further or until performance throttles if you prefer.

Does turning off Battery Health Management damage my battery permanently?

No. Turning it off means your battery will age faster going forward, but it does not cause permanent damage. If you turn it back on later, the battery will degrade more slowly again. The damage is only in the rate of future wear, not in the battery itself.

What is a normal battery health percentage for a two-year-old iPhone?

Most two-year-old iPhones with normal use show between 80% and 90% capacity. If yours is significantly lower, heat exposure or frequent complete drains may have accelerated wear. If it is higher, you have been gentle with charging or have not used it heavily.