Battery Runtime Calculator

Accurately calculate your battery runtime!

Nominal Battery Voltage:

Battery Capacity:

Battery Capacity (Wh):

Load Voltage:

Load Current:

Load Power:

Remaining Battery Capacity (%):

Runtime:

Please fill in the fields!

How to Use the Battery Calculator?

This calculator helps you estimate how long your battery can power your device.

This calculator should serve as a guideline only! Before doing electrical installations yourself, contact a certified electrician (for example, VedroVilL!)

Usage Instructions:

Nominal Battery Voltage (V): The voltage of the battery cells, usually 3.7 V for lithium-ion batteries.
Battery Capacity (Ah or Wh): Enter the battery capacity in ampere-hours (Ah) or watt-hours (Wh).
Load Voltage (V): The voltage of your device (e.g., 5 V for USB).
Load Current (A) or Power (W): Enter the current or power consumption of your device.
Remaining Capacity (%): The charge level at which most power banks automatically shut off (typically 15%).

Important Notes:

Most power banks use lithium-ion cells with a nominal voltage of 3.7 V, but the output voltage is typically 5 V (USB) or higher (e.g., 12 V/24 V for USB-C PD).

If the battery capacity is specified in mAh, it applies to the cell voltage. The calculator accounts for these conversions accordingly.

Fill in the appropriate fields, select the units, and the calculator will estimate the runtime of your device based on the battery capacity.

Of course, this calculator also works for other batteries, not only powerbanks!