Where to find battery health on your phone
Your phone tracks how much capacity your battery has lost over time and stores this information where you can see it. On iPhone, this lives in Settings under Battery. On Android, the location depends on your manufacturer — Samsung phones put it in Settings under Device Care or Battery, while Google Pixel phones show it in Settings under Battery. The number you see is a percentage: 100% means the battery is new, and anything above 80% means your battery is still in good working condition.
The reason this matters is that batteries degrade with every charge cycle, and knowing the current state tells you whether your phone will hold a charge through a full day or whether you should start thinking about replacement. A battery at 50% capacity might still power your phone, but it will drain much faster than it did when new.
Key Takeaways
- iPhone battery health appears in Settings > Battery > Battery Health & Charging as a percentage of original capacity.
- Android phones show battery health in different locations depending on the manufacturer — check Settings > Device Care on Samsung or Settings > Battery on Google Pixel.
- A battery above 80% capacity is considered healthy; below 80% means noticeable degradation has begun.
- Battery health naturally declines with use, and checking it helps you decide whether to replace the battery or the phone.
How to check battery health on iPhone
Open Settings and tap Battery. Then tap Battery Health & Charging. You will see a percentage labeled "Maximum Capacity" — this is your battery health. Below that, you may see a message about battery condition. If your battery is in good shape, it will say "Your battery is in normal condition." If degradation has reached a point where Apple recommends service, it will say "Service Recommended" or "Service Battery."
You will also see a section called "Charging Optimization" that shows whether your phone is using optimized battery charging. This feature slows charging to 80% overnight if you charge while sleeping, which slows future degradation. You can turn it on or off here, though leaving it on extends battery lifespan.
How to check battery health on Samsung Android
Open Settings and tap Device Care. Tap Battery. You will see your current battery percentage at the top, and below that a section labeled "Battery Health" or "Battery Status" showing the health as a percentage. Samsung also shows battery temperature and voltage here, but the percentage is the number that matters for understanding degradation.
If you do not see Battery Health in the Device Care menu, your phone model may not display this information. Older Samsung phones sometimes omit this feature, though most models from the last five years include it.
How to check battery health on Google Pixel
Open Settings and scroll down to Battery. Tap Battery Usage or Battery Health. Google Pixel phones display battery health as a percentage of original capacity. The screen also shows your current battery percentage and estimated time remaining, but the health percentage is what tells you about long-term degradation.
Some Pixel models show battery health only after the phone has been in use for a certain period — usually at least a few weeks. If you just got your phone and do not see a health percentage yet, check back after a few weeks of normal use.
What the numbers mean
Battery health between 100% and 80% is normal wear. Your phone will still charge fully and run through a full day without problems. This is the range where most phones spend their first two to three years of use.
Battery health between 80% and 60% means noticeable degradation has started. Your phone will still work, but you may notice it drains faster than it used to, especially if you use demanding apps or have many background processes running. You might need to charge more often, but replacement is not urgent unless battery life has become a real problem for your daily routine.
Battery health below 60% means significant degradation. Your phone may shut down unexpectedly even when the battery percentage shows 20% or 30% remaining, because the battery cannot deliver power fast enough to run the phone. At this point, replacing the battery or the phone becomes practical rather than optional.
Why battery health declines
Every time you charge your phone, the battery goes through a charge cycle. A cycle is a full discharge and recharge, though it does not have to happen all at once — charging from 0% to 100% counts as one cycle, but so does charging from 50% to 100% twice. After hundreds of cycles, the chemical compounds inside the battery degrade and hold less charge.
Heat speeds up this degradation. Charging in a hot room, using your phone while it charges, or leaving it in direct sunlight all make the battery age faster. Cold also slows charging temporarily, though it does not cause permanent damage the way heat does. This is why battery health declines faster on phones that are regularly used while plugged in or left charging overnight in warm conditions.
When to replace your battery or phone
If your battery health is above 80% and your phone lasts a full day, there is no reason to replace anything. Keep using it normally. If health is between 80% and 60% and battery life has become noticeably shorter but still gets you through the day, you can wait. If health is below 60% or your phone shuts down unexpectedly, a battery replacement will restore most of the original performance — usually at a cost between $50 and $150 depending on your phone model.
Replacing the battery makes sense if the phone is otherwise working well and you want to keep using it. If the phone is also showing other problems — cracked screen, slow performance, software no longer supported — replacing the entire phone may be more practical than replacing just the battery.
Frequently Asked Questions
Can I improve my battery health once it has degraded?
No. Battery degradation is permanent and chemical. You cannot restore capacity that has been lost. You can slow future degradation by avoiding heat, not leaving the phone plugged in constantly, and using optimized charging features, but the health percentage will not go back up.
Why does my battery health show different numbers on different days?
Battery health can fluctuate slightly day to day based on temperature, charge cycles, and how the phone calculates the measurement. Small changes of 1% to 3% are normal and not a sign of sudden failure. Large drops over a few days suggest a real problem and warrant a replacement.
Is it bad to leave my phone charging overnight?
Modern phones have optimized charging that slows charging to 80% overnight, so leaving it plugged in does not cause the damage it once did. However, if your phone is in a warm room or the charger generates heat, overnight charging still degrades the battery faster than charging during the day in a cool space.
What is the difference between battery health and battery percentage?
Battery percentage is how much charge is in the battery right now — 50% means half full. Battery health is how much total capacity the battery has compared to when it was new — 80% health means the battery can only hold 80% of its original maximum charge, even when fully charged.
Do I need to replace my phone if battery health drops below 80%?
No. Battery health below 80% is normal after a year or two of use. You only need to replace the battery or phone when the degradation affects your daily life — when the phone will not last a full day, or when it shuts down unexpectedly.