Battery capacity is not the same as battery life

Capacity stores energy; the product spends it

Battery capacity describes how much charge or energy a battery is designed to store. Runtime depends on how quickly the rest of the product consumes that energy.

A brighter display, faster processor, cellular signal, background software and temperature can all change endurance.

Compare within the same product class

Capacity is most useful when two products use similar form factors and operating conditions. Comparing a phone in mAh with a laptop in Wh would not produce a meaningful winner.

• Keep units consistent.
• Check the stated test conditions.
• Use manufacturer runtime claims as claims, not guarantees.

Read charging separately

Charging power and quick-charge playback answer a different question: how quickly useful runtime can be restored. A product can have a large battery and still charge slowly.