How to Check Battery Health on Android (2026): Built-in Tools, AccuBattery & When to Replace

By Auraz Tech Editorial Team | October 2026

Your phone used to last a full day on a single charge, and now it begs for the charger by evening — even though you haven't changed how you use it. That is not your imagination: lithium-ion batteries physically wear out with every charge cycle, and after a year or two your phone's battery holds less energy than the day you bought it. The good news is that Android gives you several ways to measure exactly how much capacity is left, from built-in settings panels and hidden dialer codes to the popular AccuBattery app and a developer-level command that reads the battery's own sensors. In this guide, we walk through every working method for 2026 — organized from easiest to most precise — and finish with the honest truth about when a battery is worth replacing and when it is time for a new phone instead.

Illustration of an Android smartphone displaying a battery health gauge and capacity ring on a circuit-board background

What Battery Health Actually Means

"Battery health" is simply the battery's current maximum capacity compared to the capacity it had when it was brand new. If your phone shipped with a 5,000 mAh battery and it can now only hold 4,200 mAh, its health is 84%. Android reports it as a percentage, and that number only ever moves in one direction: down.

Wear happens through charge cycles — one cycle equals a full 100%-worth of discharge, which can be split across several partial charges. Most modern batteries are rated for roughly 500 to 800 cycles before dropping to 80% health, which is why a heavily used phone often feels tired after 18 to 24 months. Heat is the other great accelerator: charging a phone in a hot car or under a pillow ages the battery far faster than normal charging ever could. A battery that stays cool and mostly lives between 20% and 85% charge degrades dramatically more slowly than one that is constantly fast-charged from 0 to 100 in a warm room.

It is worth separating battery health from two lookalike problems. A battery drain issue — where apps chew through a charge too fast — is a software problem you can fix, while degraded health is a chemistry problem you can only measure. And the percentage at the top of your screen is the charge level (how full the battery is right now), which says nothing about health (how big the battery still is). You can have 100% charge on a battery with 70% health — it just holds 70% of the energy it used to.

Method 1: Check Battery Health in Settings (Easiest)

Recent versions of Android have finally added a native battery health readout, which makes this the method to try first.

Google Pixel and stock Android (Android 14 and newer)

Open Settings and tap Battery.
Tap Battery health.
You will see a status such as "Normal" along with the estimated remaining capacity as a percentage of the original.

Pixels running the latest updates show this panel directly. If you do not see it, your phone may need a system update — Google rolled it out progressively.

Samsung (One UI)

Samsung does not show a health percentage in the main battery menu, but it offers the next best thing:

Open Settings > Battery.
Tap Battery protection (on older One UI versions, look under More battery settings). This screen includes the Maximum charge limit option — set it to 85% to dramatically slow future wear.
For a health reading, open the Samsung Members app, go to Support > Phone diagnostics > Battery status. A result of "Good" or "Normal" means healthy; "Bad" means the battery has degraded enough to consider replacement.

Xiaomi, Redmi, Poco (HyperOS / MIUI)

Go to Settings > Battery and look for Battery health or Battery usage details on newer HyperOS builds. Some models report an estimated capacity percentage here. If your model does not show it, jump to the AccuBattery method below — it works on every Xiaomi phone.

Method 2: The Hidden Dialer Code

Android has a built-in testing menu that many phones still support:

Open your Phone / dialer app.
Type *#*#4636#*#* (no need to press call).
Tap Battery information.

You will see the battery status, health ("Good" is normal), voltage, temperature, and sometimes the charge level technology. It does not give a precise health percentage on most phones, but a reading of "Overheat" or "Dead" here is a red flag that matches the warning signs listed later in this guide. Note that some manufacturers — notably newer Samsung and Huawei devices — disable this code, in which case nothing will happen when you type it.

Method 3: Manufacturer Diagnostics Apps

Several brands ship their own diagnostic tools that test the battery directly:

Samsung Members: as described above, the phone diagnostics suite tests battery status in under a minute.
Xiaomi: dial *#*#6485#*#* on many MIUI/HyperOS devices to open a battery information page showing charge cycles and capacity estimates.
OnePlus: recent OxygenOS builds include battery health under Settings > Battery > Battery health.
Oppo / Vivo / Realme: check Settings > Battery for a health or "battery lifespan" entry on ColorOS 14 and Funtouch OS 14+.

These tools read the battery's own fuel-gauge chip, so their numbers are trustworthy. If your brand offers one, its reading is the answer you should believe.

Method 4: AccuBattery (Most Detailed, Works Everywhere)

AccuBattery is the most popular battery health app on the Play Store, and it works on any Android phone regardless of brand. Instead of reading a single number, it measures your battery by tracking how much charge enters during each session and comparing it against the design capacity.

Install AccuBattery from the Play Store (the free version is enough).
Open it, grant the requested permissions, and let it run in the background.
Charge your phone from below 20% to 100% a few times over the next several days. AccuBattery needs at least 3 to 5 full charge sessions before its health estimate becomes reliable.
Open the Health tab to see your battery's estimated capacity in mAh and as a percentage of the design capacity.

Two tips make a real difference here. First, do not judge the number after a single charge — early readings swing wildly and settle down with more data. Second, the free app also tracks per-app discharge rates, which makes it excellent at answering the related question of what is draining your battery, not just how healthy it is. About AccuBattery's own battery cost: it reads the system's existing charge counters rather than polling sensors continuously, so its background impact is negligible.

Method 5: The ADB Command (Exact Numbers for Nerds)

If you have a computer and a USB cable, Android Debug Bridge gives you the rawest possible data — straight from the battery's fuel-gauge chip:

On your phone, enable Developer options (Settings > About phone > tap Build number seven times), then enable USB debugging.
On your computer, install ADB (it comes with Android's free platform-tools) and connect the phone via USB. Accept the debugging authorization prompt on the phone.
Run: adb shell dumpsys battery

Look for two fields: charge counter (current charge in microampere-hours) and, on many devices, mSavedBatteryAsoc or similar state-of-health entries. Comparing the charge counter at full charge against your model's design capacity gives you a DIY health percentage. This method is overkill for most people, but it is the ground truth that apps like AccuBattery are ultimately estimating — and it works on any phone, rooted or not.

7 Warning Signs Your Battery Health Is Degraded

You do not always need an app to tell you something is wrong. These symptoms almost always point to a worn battery rather than a software problem:

The percentage drops suddenly — your phone falls from 40% to 15% in minutes, or dies while still showing 20%+. This is the classic sign of a battery whose voltage collapses under load.
It shuts off in the cold — degraded batteries are far more sensitive to low temperatures and may power off outdoors in winter even at half charge.
Charging takes much longer — or the percentage stalls and jumps erratically while plugged in.
The phone gets hot during normal charging — warmth is normal, but a phone that becomes uncomfortably hot every charge is struggling.
The back panel is bulging — a swollen battery is a safety issue. Stop using the phone, do not puncture it, and get it replaced immediately at a service center.
It only lasts a few hours despite a fresh factory reset and no heavy apps — ruling out software drain leaves the battery itself.
Battery saver is permanently on just to survive the day — a coping strategy that confirms the underlying problem.

If you recognize two or more of these, measure your health percentage with one of the methods above to confirm before spending money on a replacement.

What to Do When Battery Health Drops Below 80%

The industry rule of thumb — used by Apple, Samsung, and independent repair shops alike — is that a battery below 80% of its original capacity is due for replacement. At that point, runtime frustration is real: the phone dies before dinner, reboots under heavy load, and no amount of battery-saver tweaking truly fixes it.

The good news: on a phone that is otherwise fine — fast enough, cameras good, software still updated — a fresh battery is one of the best-value repairs in tech. A new battery typically restores a two-to-three-year-old phone to nearly its original endurance, and the repair costs a fraction of a new device. Always prefer an authorized service center or a reputable repair shop using genuine or OEM-grade batteries; ultra-cheap third-party batteries often have inflated capacity claims and inferior safety circuitry, and a bad battery can damage the phone it is supposed to save.

When replacement is not the answer: if the phone no longer receives security updates, the screen is cracked, or the repair costs more than a third of a comparable new phone, the sensible move is upgrading rather than reviving. A new battery cannot fix an obsolete phone.

And regardless of your decision, start protecting your next battery today: enable the 85% charge limit (Settings > Battery on Samsung, Pixel, and most 2024+ phones), keep the phone out of direct sun and hot cars, and avoid heavy gaming while fast-charging. These three habits add more months to a battery's life than any "optimizer" app ever will.

Battery Health Myths, Debunked

"You must fully drain a new phone before first use." That was nickel-cadmium advice from the 1990s. Lithium-ion batteries have no memory effect — charge your new phone however you like.
"Battery calibration apps restore lost capacity." Calibration only resets the phone's percentage display so it reads accurately. It cannot reverse chemical wear; the actual capacity stays exactly the same.
"Closing background apps preserves battery health." It saves a little charge in the moment, but health is about total cycles and heat over months. Aggressively killing apps has almost no effect on long-term degradation.
"Only charge with the original charger." Any quality charger with the correct USB standard is fine. What matters is heat and charge speed — a cheap no-name fast charger that runs hot is the real enemy, not the brand on the brick.
"Wireless charging ruins batteries." Wireless charging generates slightly more heat than wired, which adds a small amount of wear — but modern phones manage it well, and the difference is minor compared to the damage done by heat from, say, charging in direct sunlight.

FAQ

What is a good battery health percentage on Android?

Anything above 85% of the original design capacity is considered good. Most phones feel new down to about 85%, noticeably weaker between 75% and 85%, and genuinely frustrating below 75%. Manufacturers and service centers generally recommend a replacement once health drops below 80%.

Can I check battery health on Android without installing an app?

Yes. Pixels and phones running Android 14 or newer show a Battery health panel in Settings > Battery. Samsung devices can run diagnostics through the Samsung Members app. The dialer code *#*#4636#*#* also reveals battery information on many phones, and the ADB command "adb shell dumpsys battery" works on any Android phone connected to a computer.

Does AccuBattery itself drain the battery while measuring?

Its impact is negligible — AccuBattery does not poll sensors continuously; it reads the system's existing charge measurements during charge sessions. It only becomes accurate after several full charge cycles, but it will not noticeably affect your battery life in return.

At what battery health should I replace my phone battery?

Replace the battery when health falls below 80% of the original capacity, or sooner if the phone shuts down unexpectedly, swells, or overheats during charging. Below 80%, degraded runtime and voltage drops start causing real daily frustration — a fresh battery usually makes a two-to-three-year-old phone feel like new again.

Can a degraded battery be fixed without replacing it?

No — chemical degradation inside a lithium-ion cell is irreversible. Software tricks like "battery calibration" only reset the phone's percentage display, not the actual capacity. The only true fix for a worn battery is a physical replacement.

Does charging overnight damage battery health?

Modern phones stop charging at 100% and top up trickle-wise, so overnight charging is far less harmful than it used to be. What does accelerate wear is heat and keeping the battery pinned at 100% for hours in a hot room. Enabling the 85% charge limit or adaptive charging feature protects health far more than unplugging before bed.

Auraz Tech Editorial Team — we test every guide on real devices and keep our tutorials updated.