On Windows, run powercfg /batteryreport in Terminal and compare "Full charge capacity" with "Design capacity". On a Mac, open System Settings, then Battery, then Battery Health and read Maximum Capacity. Divide today's capacity by the original to get a health percentage. When it falls well below 80 percent and runtime has noticeably shrunk, plan a replacement.
How do you check battery health on Windows?
Windows doesn't show a battery health figure in Settings on most builds, but it has a hidden report that gives you the real numbers. It takes about a minute, needs no downloads, and works on Windows 10 and Windows 11 alike. Follow these steps.
- Right-click the Start button and open Terminal, or search for Command Prompt.
- Type powercfg /batteryreport and press Enter.
- Windows prints the location of the file it created, usually named battery-report.html. Open that file in your browser.
- Under "Installed batteries", find Design capacity and Full charge capacity, both shown in mWh.
- Divide the full charge figure by the design figure and multiply by 100.
For example, if the design capacity is 50,000 mWh and the full charge capacity is now 40,000 mWh, the battery holds 80 percent of its original capacity. The same report lists the cycle count on laptops that report it, though some models leave that field blank.
Reading the rest of the report
Below the capacity figures, the report adds several useful sections. "Recent usage" and "Usage history" show when the laptop ran on battery and when it was plugged in. "Battery capacity history" charts how full charge capacity has fallen over time, which makes rapid ageing obvious. "Battery life estimates" compares the design capacity with the full charge capacity as runtime, at the usage seen during the report.
Treat the estimates as a guide, because they depend on how you used the laptop during that period. The capacity history is the more reliable section. If the line drops steeply within a few months, the battery is ageing faster than normal, which is common when it runs hot or sits at 100 percent for long periods.
Other ways to check on Windows
Most laptop makers include their own tool. Lenovo Vantage, MyASUS, Dell's power and support apps and HP's support software each show battery condition, and many offer a charge limit. Many business laptops also show battery information inside the BIOS or UEFI screen, which is handy when Windows won't start. These tools sometimes use different wording, such as "Good", "Fair" or "Replace soon", but the underlying idea is the same capacity comparison.
How do you check battery health on a Mac?
macOS puts the numbers in plain sight. On macOS Ventura and later, open the Apple menu, choose System Settings, click Battery and open the information button beside Battery Health. You'll see the battery's condition, normally "Normal" or "Service Recommended", and Maximum Capacity as a percentage compared with when the battery was new. On older macOS versions, hold Option and click the battery icon in the menu bar to see the condition.
For more detail, hold Option, click the Apple menu and choose System Information. Under Power, you'll find the cycle count, condition and, on newer Macs, maximum capacity. Apple says recent MacBook batteries are designed to keep up to 80 percent of their original capacity at 1,000 complete charge cycles, although older models are rated for fewer. A free third-party tool such as coconutBattery can also show design and current capacity.
Which numbers count as healthy?
There's no official line that triggers a replacement, and manufacturers use different wording. The table below is our rough guide for everyday laptops, based on how batteries tend to behave, not a manufacturer rule. Judge by runtime too, because the way you use the laptop matters as much as the percentage.
| Health reading | What it usually means | What to do |
|---|---|---|
| Around 90 percent or more | Battery is in good condition | Nothing; keep good charging habits |
| 80 to 90 percent | Normal ageing; slightly shorter runtime | Monitor every few months |
| 60 to 80 percent | Runtime is clearly shorter; sudden drops possible | Plan a replacement if you rely on battery power |
| Below 60 percent | Often unreliable; may shut down without warning | Replace it |
| Any reading, plus swelling or heat | Safety issue | Stop using it and replace it at once |
If you mostly work plugged in, a worn battery is a nuisance rather than a problem. If you carry the laptop around, the usable runtime matters more than the number on screen.
What other signs show a battery is failing?
The report can look fine while the battery misbehaves, and the reverse is also true. Watch for symptoms that numbers don't capture.
- The laptop shuts down suddenly at 20 to 40 percent, or the moment you unplug the charger.
- The percentage jumps, for example from 60 straight to 30, or stays stuck for a long time.
- Runtime has halved compared with a year ago, with the same use.
- The base is hot near the battery, even at light use.
- The case bulges, the touchpad lifts or the lid won't sit flat. This is a swollen battery. Stop charging it and read our guide to swollen laptop batteries.
- Windows or macOS warns you to "service" or "replace" the battery.
Our guide on signs a laptop battery needs replacement goes through these in more detail.
How can you slow down battery wear?
Lithium-ion cells age with heat, time and deep charge cycles, and you can't stop that, but you can slow it. These habits help most.
- Use a charge limit if you work plugged in. Many laptops let you cap charging at around 80 percent in the maker's app or BIOS. On a Mac, keep Optimized Battery Charging on.
- Keep it cool. Heat is the biggest enemy. Don't leave the laptop in a parked car or a hot bag, and keep the vents clear.
- Avoid running it flat repeatedly. Partial top-ups are gentler than regular drops to zero.
- Use the right charger. A properly rated charger avoids stress that cheap adapters cause.
- Don't store it at 100 percent or empty for months. A middle level is better for long storage.
We cover this further in our guide on making a laptop battery last longer.
When should you replace the battery, and what does it cost?
Replace it when runtime no longer fits your needs, when capacity is well down and the laptop shuts off unexpectedly, or at the first hint of swelling. Replacement is almost always cheaper than replacing the laptop. An indicative range for Windows laptops is ₹1,499 to ₹4,999, and for MacBooks ₹3,499 to ₹6,999. The exact price depends on the model, whether the battery is screwed in or glued, and the quality of the cell.
On many Windows laptops the battery is a screwed-in internal pack. On MacBooks and some thin ultrabooks, it is bonded into the case, which makes the job more delicate and is why those cost more. Our pages on laptop battery replacement and MacBook battery replacement explain the work, and our battery cost guide lists what drives the price. The ₹350 inspection fee is credited back if you proceed, and the quote is given in writing beforehand.
Frequently asked questions
How often should I check my laptop battery health?
Every three to six months is plenty for most people. Check sooner if runtime drops suddenly or the laptop shuts down unexpectedly.
Is 80 percent battery health bad?
No. Eighty percent is a normal sign of ageing after a couple of years of use. You'll notice shorter runtime, but the battery is still useful. The trouble starts when it falls much lower or shows sudden drops.
Does the battery report work on every laptop?
It works on nearly all Windows laptops, but some don't report the cycle count and a few report odd numbers. If the figures look wrong, compare them with the maker's app.
Can I recalibrate a battery to bring the health back?
Recalibration can fix an inaccurate percentage gauge, but it can't restore lost capacity. Worn cells need replacing.
A low capacity figure isn't an emergency, but a swollen case is. If the report shows heavy wear, or the base is bulging, book a free pickup or call +91 74997 61196 and we'll quote the replacement for your model in writing. We cover Mumbai, Thane, Vasai-Virar and Palghar.
