How to choose average watts
Laptop runtime depends on display brightness, CPU/GPU load, wireless radios, attached devices, battery age and thermal limits. Use a low draw for writing or browsing, a medium draw for video calls, and a high draw for gaming, rendering or heavy development work.
Example
A 60 Wh battery drawing an average of 10 W with a 10% reserve has 54 Wh usable energy, which estimates about 5.4 hours of runtime. The estimate is a planning number, not a battery health test.
Common mistakes
Do not use the laptop charger wattage as average power draw. The charger rating is a maximum supply capacity, not normal battery use.
Last reviewed: 2026-05-17