Phone buying guide
Phone battery capacity: what mAh can and cannot tell you
Use capacity as one input without mistaking it for a complete battery-life measurement.
Capacity is stored charge, not runtime
Milliamp-hours describe nominal charge capacity under specified conditions. Runtime also depends on voltage, display power, processor efficiency, radio conditions, background activity, temperature, and software. Two phones with equal capacity can therefore finish the same workload at different times.
Capacity remains useful when comparing closely related models because many other variables are similar. Across unrelated platforms it should be treated as a hardware constraint, not a battery-life score.
Manufacturer tests answer narrower questions
Video-playback or mixed-use claims describe a defined test, often with controlled brightness and connectivity. They help within one manufacturer’s lineup but are not automatically comparable across brands with different methods.
A responsible comparison keeps the published capacity and runtime claim separate, identifies the test owner, and avoids converting one into the other.
Choose for the workload
Navigation, gaming, camera recording, hotspot use, weak cellular coverage, and high outdoor brightness are demanding workloads. Buyers with those habits should prioritize tested endurance, charging access, and battery health—not capacity alone.
Long ownership also makes replacement cost and software battery-health tools relevant. A slightly smaller replaceable or serviceable battery can be a better long-term choice.
Editorially reviewed: July 20, 2026