Every laptop battery slowly loses capacity. After a few hundred cycles, a battery that once lasted 10 hours might only last 7. Here’s how to see exactly how worn yours is, on Windows or Mac, using tools that are already built in.
In this article
Windows 11 and 10: the battery report
- Right-click the Start button and choose Terminal (or Command Prompt / PowerShell).
- Type this and press Enter:
powercfg /batteryreport /output "%USERPROFILE%\Desktop\battery-report.html"
(In PowerShell, usepowercfg /batteryreport /output "$env:USERPROFILE\Desktop\battery-report.html".) - Open battery-report.html from your desktop in any browser.
- Under Installed batteries, compare:
- Design capacity: what the battery held when new
- Full charge capacity: what it holds now
- Cycle count: how many full charge cycles it’s been through (not reported by every laptop)
Battery health = full charge capacity ÷ design capacity. For example, 42,000 mWh ÷ 56,000 mWh = 75%.
Scroll further for Battery capacity history (how fast it’s wearing) and Battery life estimates (runtime at full charge versus when new).
Manufacturer apps (easier)
- Lenovo Vantage: Device → Power shows battery condition and cycle count.
- MyASUS: Customization → Battery Care or System Diagnosis.
- Dell Power Manager / SupportAssist: battery health status.
- HP Support Assistant: Battery check (Troubleshooting & fixes).
- Surface app: Battery & charging.
Mac
- Open System Settings → Battery.
- Click the (i) next to Battery Health to see the condition (Normal or Service Recommended) and Maximum Capacity.
- For the cycle count, hold Option, click the Apple menu, choose System Information, then Power. Look for “Cycle Count”.
Note: the old trick of Option-clicking the battery icon in the menu bar no longer shows battery condition in current macOS versions.
What the numbers mean
| Health | What to expect |
|---|---|
| 90–100% | Like new. |
| 80–90% | Normal wear for a laptop that’s 1–3 years old. Noticeably shorter runtime, but fine. |
| Below 80% | Most manufacturers consider the battery worn. Replacement worth considering if runtime bothers you. |
| Below 60%, or sudden shutdowns | Replace it. Unexpected shutdowns at 20–30% often mean a failing cell. |
Most laptop batteries are rated for roughly 300–1,000 cycles before reaching 80%. Apple rates current MacBooks for 1,000 cycles.
Signs of a failing battery (no software needed)
- The percentage drops in sudden jumps, or the laptop dies well above 0%.
- Runtime has dropped dramatically compared with when it was new.
- The laptop only works while plugged in, or Windows shows “Plugged in, not charging” when no charge limit is set.
- Physical swelling: a lifting trackpad, a gap in the case, or the laptop rocking on a flat table. Stop using it and get the battery replaced. Swollen lithium batteries are a fire hazard.
Replacing a laptop battery
For MacBooks, use Apple or an Apple Authorised Service Provider (the price is fixed and lower with AppleCare+). For Windows laptops, buy a genuine battery from the manufacturer’s parts store using your exact model number. Cheap third-party batteries often have lower real capacity and weaker safety circuits. Business laptops like ThinkPads and Dell Pro models are usually easy to do yourself with a screwdriver.
Slow down future wear with a charge limit, and get more from the battery you have with these battery life tips.
Battery not charging? See laptop plugged in but not charging.
