How to Check Your Phone Battery Health on iPhone and Android in the UK

Every phone battery wears out slowly, and after a year or two you may notice shorter battery life or sudden shutdowns. Checking battery health tells you how much capacity your battery has left compared with when it was new. It takes less than a minute, and it helps you decide whether a settings change, a new charging habit, or a battery replacement is the right next step. This guide covers iPhone and Android, with the differences that matter in the UK.

Battery health is not the same as the percentage shown at the top of your screen. That number shows how much charge is left right now. Battery health shows how much charge the battery can hold in total. A phone that charges to 100% may still hold far less energy than it did when new, which is why it can run flat by mid afternoon even though the battery meter looks fine.

Step 1: Check battery health on iPhone

On iPhone, open Settings, then tap Battery, then Battery Health and Charging. You will see a figure called Maximum Capacity, shown as a percentage. A new iPhone shows 100%. After normal use, that number falls slowly. Apple treats a battery as worn when it drops to around 80%, which is often the point where you will notice much shorter life between charges.

On the same screen, you may see a message about battery health, such as Normal or Service Recommended. Normal means the battery is still supporting peak performance. Service Recommended means the battery has worn enough that Apple suggests a replacement, though the phone will keep working. In most recent versions of iOS, you will also see charging options on this screen, including optimised charging, which slows charging past 80% to reduce wear.

If you do not see a Battery Health option, check that your iPhone software is up to date, since older versions show less detail. Very old iPhones may show only basic battery usage without a health percentage.

Step 2: Check battery health on Android

Android does not have one single battery health screen, so the steps depend on your phone brand. On many Samsung phones, open Settings, then Battery and Device Care, then Diagnostics, then Battery Status, if your model offers it. You may see a simple rating such as Good, Normal or Weak rather than a percentage.

On Google Pixel phones, open Settings, then Battery, then Battery Health, where newer models show capacity as a percentage. On other Android phones, look under Settings, then Battery, then Battery Usage or Battery Health. If no health figure appears, your phone maker may not show one directly, which is common on older or budget models.

In that case, a free battery app from the Play Store can estimate health, but treat those estimates with care. They usually need a few full charge cycles before they settle.

Step 3: Understand what the numbers mean

A maximum capacity of 90% or above usually means the battery is still in good shape, and any short battery life is more likely caused by settings, apps or signal problems. Between 80% and 89%, you will probably notice shorter life, especially on busy days, but the phone should still be usable with a few tweaks.

Below 80%, the battery is classed as worn. You may see faster drops, unexpected shutdowns in cold weather, or a phone that struggles to last a full day even with light use. That does not mean the phone is broken. It means a replacement battery, if available for your model, is likely to make a bigger difference than any settings change.

Also check how the battery behaves, not just the number. A phone at 85% that drops from 30% to zero in minutes has a different problem from a phone at 85% that fades steadily.

Step 4: Improve battery life before you replace anything

Before spending money, try the fixes that help most phones. Lower screen brightness or turn on auto brightness, shorten the screen timeout, and turn off background refresh for apps you rarely use. Location services, especially precise location for many apps, can also drain power, so set location access to While Using the App where possible.

Check which apps use the most power under Battery Usage in Settings. A single app that runs in the background all day can matter more than battery age. Updating apps and phone software can help too, since updates often fix power hungry bugs. If you charge overnight, keep optimised charging on, since holding a battery at 100% for hours speeds up wear.

Step 5: Decide about a battery replacement in the UK

If your battery health is below 80%, or if the phone no longer lasts a normal day, a replacement is worth considering. For iPhones, Apple Stores and authorised service providers can replace batteries, and many independent repair shops in the UK offer the same service. For Android phones, the maker, your network, or a local repair shop can usually help, though prices and availability vary by model.

Ask for a clear quote before agreeing, including whether the replacement battery is genuine or a quality third party part, and what warranty comes with the work. Keep your receipt, since a good repairer will usually offer at least a few months of cover. Back up your phone before handing it over, even for a battery job, since repairs can sometimes require a reset.

If the phone is old and a replacement costs a large share of its value, it may make more sense to keep using it with a portable charger, or to plan a replacement phone instead.

Frequently Asked Questions

What is a good battery health percentage?

Above 90% is generally good, 80% to 89% is fair and usually still usable, and below 80% is classed as worn. The exact point where you notice problems depends on how heavily you use the phone each day.

Does fast charging damage battery health?

Fast charging adds some wear over time, but modern phones manage heat and charging speed to limit it. Using optimised charging, avoiding very hot conditions, and not leaving the phone on charge at 100% for long periods will help more than avoiding fast charging entirely.

Can battery health go back up?

No. Battery health only falls with use and age, and it cannot be restored by an app, a reset or a special charging method. If a reading jumps up after a software update, that is usually a recalibration of the estimate, not a real recovery.