Is my laptop battery dying?
Your laptop can tell you objectively: both Windows and macOS can generate a battery report comparing current maximum capacity to the battery's original design capacity. A big gap between the two means normal aging, not a fault — and is the honest signal for whether a replacement is worthwhile.
How to check battery health yourself
On Windows, running a battery report from the command line produces a page showing design capacity versus current full-charge capacity. On a Mac, battery health and cycle count are visible directly in system settings. Either way, you get a real number instead of guessing from how the laptop 'feels'.
A battery that's dropped well below its original capacity will show shorter runtime and sometimes faster percentage drops — both are consistent with normal wear, not necessarily a defect.
What actually wears a battery out
Lithium-ion batteries degrade gradually through charge cycles and heat over years of normal use — this is expected, not a fault. Leaving a laptop plugged in constantly is not the main culprit modern batteries are designed to stop charging past 100%. Consistently running hot, or being fully drained repeatedly, ages a battery faster than staying plugged in does.
When it's a genuine safety concern
A battery that's simply lost capacity is safe to keep using, just less convenient. A battery that's swollen — a bulging trackpad, keys that no longer sit flat, or a case that won't close properly — is a different situation entirely and should be stopped using and replaced promptly.
Key takeaways
- Check real battery health with a built-in report before assuming the worst.
- Capacity loss over years is normal wear, not necessarily a defect.
- Being plugged in constantly isn't the main cause of battery wear on modern laptops.
- A swollen battery is a safety issue — stop using it and replace it promptly.
Laptop battery health — common questions
1. How can I check my laptop's battery health myself?
Windows and macOS both have built-in battery reports that show current maximum capacity against the battery's original design capacity. A significant gap between the two is a sign of normal aging, not a fault.
2. Does it damage a laptop battery to leave it plugged in all the time?
Modern laptop batteries and charging circuits are designed to handle being plugged in constantly, and most stop charging past 100% rather than overcharging. Battery wear over years is mostly a function of charge cycles and heat, not simply being plugged in.
3. When is a laptop battery worth replacing versus living with it?
If a battery-health check shows significantly reduced capacity and the runtime no longer suits how you use the laptop, replacement is usually worthwhile — especially since batteries are a contained, replaceable part on most laptops.