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battery capacity converter

Battery Capacity Converter

Power banks and battery packs are often labeled in mAh or Ah, while runtime math needs Wh. Convert the label first, then size the load.

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Voltage presets

Use the voltage printed on the battery label when available. mAh without voltage cannot be compared fairly.

Converted capacity

27,027 mAhConverted capacity: 27,027 mAh

mAh = Wh x 1000 / volts

Watt-hours100 Wh
Amp-hours27.03 Ah
Milliamp-hours27,027 mAh
Voltage3.7 V
Travel check: At or below 100 Wh, lithium-ion spare batteries are within the standard FAA PackSafe size limit, but airline, route, and damage-protection rules still apply. Check the FAA PackSafe lithium battery page and your airline before flying with spare batteries or power banks. Reviewed 2026-06.
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WattRunTime.com

WattRunTime battery capacity conversion

Converted capacity27,027 mAh
ModeWh to mAh
Watt-hours100 Wh
Voltage3.7 V
Result27,027 mAh

WattRunTime battery capacity conversion

  • WattRunTime battery capacity conversion
  • Mode: Wh to mAh
  • Input: 100 Wh
  • Voltage: 3.7 V
  • Result: 27,027 mAh
  • Watt-hours: 100 Wh
  • Travel note: At or below 100 Wh, lithium-ion spare batteries are within the standard FAA PackSafe size limit, but airline, route, and damage-protection rules still apply.
  • Use the voltage printed on the battery label when available. mAh without voltage cannot be compared fairly.

At or below 100 Wh, lithium-ion spare batteries are within the standard FAA PackSafe size limit, but airline, route, and damage-protection rules still apply.

Pick the conversion before the runtime math

The hub is for labels that mix Wh, mAh, Ah, and voltage. Convert to watt-hours first, then use the result in runtime, sizing, or travel checks.

Compare energy, not charge

mAh is charge. Wh is energy. Voltage is the bridge between them, so the same mAh label can mean different runtime at different voltages.

Move from label to plan

Once you have Wh, the runtime calculator can apply load watts, reserve, efficiency, and output-path losses.

Power Station Capacity Runtime Guides