How do I find my laptop's battery capacity?
Windows: Open Command Prompt and run powercfg /batteryreport, then check the HTML report.
Mac: Hold Option and click the Apple menu → System Information → Power.
Linux: Run upower -i /org/freedesktop/UPower/devices/battery_BAT0 in terminal.
Why does my actual battery life differ from estimates?
Real-world battery life varies based on many factors: background apps, WiFi/Bluetooth usage, battery age and health, ambient temperature, and specific workloads. Our estimate assumes typical conditions—your actual results may be 10-20% different.
What's a typical laptop battery capacity?
Ultrabooks: 40-60Wh (prioritizing portability)
Standard laptops: 50-70Wh
Workstations: 70-90Wh
Gaming laptops: 80-100Wh (but drain faster due to power demands)
Does battery capacity decrease over time?
Yes. Lithium-ion batteries lose capacity with age and charge cycles. After 2-3 years or 500+ cycles, most batteries retain 70-80% of original capacity. Our calculator uses your current rated capacity—if your battery is older, actual life will be lower.
How much does screen brightness affect battery life?
The display is one of the biggest power consumers. Reducing brightness from 100% to 50% can extend battery life by 15-30%, depending on your laptop. OLED screens are more efficient at lower brightness, while LCD screens have a backlight that draws similar power regardless.
Why do gaming laptops have such short battery life?
Gaming laptops use high-performance CPUs and dedicated GPUs that consume 45-150W under load—compared to 8-25W for typical productivity tasks. Even a 100Wh battery only lasts 1-2 hours during gaming. They're designed to be plugged in during intensive use.