Charging habits shape long-term battery health, and the right check shows how much capacity your battery still holds.
Your phone's battery percentage tells you how much charge is left right now, but it says nothing about how much charge the battery can still hold.
That second figure is battery health, and it quietly decides whether a two-year-old phone still lasts the day or dies before dinner.
Unlike the iPhone, stock Android has no single universal battery health percentage that appears on every phone from every brand today.
What you can check depends on your phone's maker, model, and Android version, so this guide walks through every reliable method in order.
Start with the built-in tools from Google and Samsung, then try the classic dialer code, and finish with a trusted app if needed.
Key Highlights
- Charge level is not health.
The status bar percentage only shows today's remaining charge, while health compares the battery's current full capacity against what it held when brand new.
- Pixel 8a and newer show health in Settings.
On supported Pixel phones, Settings has a dedicated Battery health page that shows the status, the estimated capacity, and charging optimisation controls in one place.
- Samsung uses Samsung Members diagnostics.
Galaxy phones run their official battery check inside the Samsung Members app, where Phone diagnostics rates the battery as Normal, Weak, or Bad after testing.
- The 4636 code works only on some phones.
Dialling *#*#4636#*#* opens a hidden Testing menu on certain models, but many modern phones ignore the code completely or no longer include battery information inside.
- Apps estimate health from real charging data.
AccuBattery measures how much charge actually flows into the battery across several charging sessions, then compares that estimate with the battery's original design capacity.
- Below 80 percent is the usual warning line.
Once estimated capacity falls under roughly eighty percent of the original figure, shorter days, surprise shutdowns, and slow performance become much more likely to appear.
Battery Health vs Charge Level: What the Numbers Mean
Battery health is a simple comparison between two capacities: how much energy the battery could store when it was new and today.
A health reading of ninety percent means a full charge now delivers roughly ninety percent of the runtime the phone originally offered when new.
The charge level, by contrast, is just a fuel gauge for today, dropping from one hundred toward zero as you use the phone normally.
Lithium-ion batteries lose capacity with every charge cycle, and one cycle means using a full battery's worth of energy, even across several partial charges.
Heat, age, and long hours spent at a full charge speed that wear up, which is why two identical phones can age very differently.
| Figure | What it tells you |
|---|---|
| Charge level | How full the battery is right now, shown in the status bar |
| Battery health | Current full capacity compared with the capacity when the battery was new |
| Cycle count | How many full charges' worth of energy the battery has delivered in its life |
| Battery status | A plain-language verdict such as Normal, Reduced, Weak, or Bad on some phones |
Method 1: Check Battery Health in Settings on a Google Pixel
Google Pixel phones from the Pixel 8a onward carry the clearest built-in health check on Android, and it takes less than a minute.
Open the Battery health page. Go to Settings, tap Battery, then tap Battery health, where the phone shows its health status and links to advice about supporting the battery.
Read the status word. The status reads Normal when capacity is healthy, Reduced when estimated capacity has dropped below eighty percent, or Unavailable when the phone cannot calculate it.
Check the estimated capacity. Tap Battery capacity on the same screen to see the estimated percentage of the original capacity that a full charge can still hold today.
Look up your cycle count. Open Settings, then About phone, then Battery information to see how many charge cycles the battery has completed since the phone was first used.
Older Pixel models do not show a health status at all, so if those menus are missing, skip ahead to the app method described below.
Some newer Galaxy phones, including the Galaxy S25 series on recent One UI versions, also show battery health and cycle count under Settings, then Battery information.
Availability depends on the model and region, so do not worry if your Galaxy hides that page and offers Samsung Members instead of it.
Method 2: Run the Samsung Members Battery Diagnostic on a Galaxy
Samsung's official check lives in the Samsung Members app, which is preinstalled on most Galaxy phones and free from the Galaxy Store or Play Store.
Open Phone diagnostics. Launch Samsung Members, tap the Support tab at the bottom, and find Phone diagnostics, then tap Get started to open the full list of hardware tests.
Run the battery test. Tap Battery status and let the diagnostic finish, because the app checks the battery alongside the phone's other components before it shows you the final result.
Read the result carefully. Normal means no battery performance issues were found, Weak means efficiency has dropped through long use or heat, and Bad means the battery has degraded significantly.
Know the alternative path. On many Galaxy models the same diagnostics also live under Settings, then Battery and device care, then Diagnostics, although names vary slightly between One UI versions.
Samsung's verdict is a plain-language rating rather than a percentage, which makes it a good official answer even though it cannot show exact capacity loss.
Method 3: Try the *#*#4636#*#* Dialer Code
For years, Android guides have shared a hidden dialer code that opens a Testing menu, and it is still worth trying on many phones.
Use the phone's own dialer. Open the stock Phone app and type *#*#4636#*#* exactly, because third-party dialer apps usually block these secret codes from running at all on the phone.
Open Battery information if it appears. On supported phones the Testing menu opens by itself, and a Battery information entry may show health, voltage, temperature, and the current charge level inside.
Do not change anything else. The same menu can contain network and radio settings, so look at the information you need and leave every setting exactly as you found it there.
On many modern phones nothing happens at all, because manufacturers, newer Android versions, and even carriers can remove or block the code for security reasons.
Even when the menu opens, recent Android versions often leave battery information out of it, so a missing result says nothing bad about your battery itself.
Method 4: Estimate Battery Health with AccuBattery
When a phone shows no health figure of its own, a measurement app is the practical fallback, and AccuBattery is the best-known option on Android.
Install it and charge normally. Install AccuBattery from the Play Store, confirm the design capacity it detects for your model, then simply use and charge the phone as you normally would.
Give it several real sessions. The estimate only becomes meaningful after several longer charging sessions, ideally charges that add more than half the battery, because one short top-up proves almost nothing.
Read the Health tab. The Health tab compares estimated capacity with design capacity to produce the health percentage, and it also shows the battery wear added by each charging session.
Use the charge alarm. Set the built-in charge alarm near eighty percent if you want a reminder to unplug, which reduces the time the battery spends at full charge daily.
Treat the figure as a careful estimate rather than an official measurement, because the app calculates capacity from charge flowing in instead of reading the battery controller.
Estimates can move after software updates or unusual charging sessions, so judge the trend across a week or two instead of reacting to one single number.
Signs Your Battery Needs Replacing
- Shorter days than before.
A phone that once finished the day comfortably but now needs a midday top-up with the same habits is showing classic capacity loss in daily use.
- Sudden shutdowns.
Powering off at twenty or thirty percent, or the percentage jumping in big steps, suggests the battery can no longer hold a stable voltage under load.
- Slow, laggy performance.
Some phones deliberately reduce peak performance as the battery weakens, so unexplained sluggishness on an older phone can be a battery symptom rather than a software fault.
- Heat and swelling.
A battery that runs unusually hot deserves attention, and any swelling that lifts the screen or back panel means you should stop using the phone immediately.
- Health below the line.
A Pixel status of Reduced, a Samsung verdict of Bad, or an app estimate stuck under eighty percent all point to a replacement being worth its cost.
Tips to Slow Down Battery Ageing
Turn on the built-in battery protection. Many phones can cap charging near eighty percent or slow the final stretch overnight, under names like Battery protection, Charging optimization, or Adaptive charging in battery settings.
Keep the phone away from heat. Heat is the battery's biggest enemy, so avoid leaving the phone in hot cars or direct sun, and remove thick cases during long fast-charging sessions at home.
Prefer partial charges on busy days. Topping up between roughly twenty and eighty percent is gentler than repeated full cycles, although using the phone normally always matters more than obsessing over every percent.
Use decent chargers and cables. A quality charger that matches your phone's standard keeps charging heat and voltage under control, while damaged cables and bargain adapters make both noticeably worse over time.
Do not drain it flat every day. Regularly running the battery to zero adds stress, so plug in when the low battery warning appears instead of squeezing out the last few minutes daily.
Frequently Asked Questions
Can every Android phone show a battery health percentage?
No, because Android leaves the feature to each manufacturer, which is why newer Pixel and some Galaxy models show one while many other phones show nothing at all.
What battery health percentage is still good?
Anything above eighty percent is generally considered serviceable, because Google itself designs recent Pixel batteries to keep about eighty percent capacity after roughly one thousand cycles.
Why does the 4636 code do nothing on my phone?
Manufacturers, Android versions, dialers, and carriers can each disable secret codes, so a silent result is normal on modern phones and not a fault with yours.
How accurate is AccuBattery's health estimate?
It is an estimate built from real charging sessions, and it grows more reliable over several charges, but only the manufacturer's own diagnostics can read the battery directly.
Is a battery replacement worth it on an older phone?
Usually yes when the phone still performs well otherwise, because a fresh battery restores the original runtime for far less money than buying a comparable new phone.
Checking battery health on Android takes a few extra steps compared with an iPhone, but the answer is there once you know where the manufacturer hid it.
Run the built-in check first, confirm it with an app if needed, and let the result, not guesswork, decide whether a replacement is due.