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E-bike range calculator

Enter your battery as watt-hours or as volts and amp-hours, how much of it you use, and how many watt-hours you burn per mile or km. Get the range per charge and see how it moves with consumption.

Battery and consumption

Battery given as

Battery energy

Enter a battery energy from 10 to 10,000 Wh.

Nominal voltage

Enter a voltage from 6 to 120 V.

Capacity

Enter a capacity from 1 to 200 Ah.

Usable share (assumption)

How much of the rated energy you use before stopping. 80% is an example value, not a battery spec. Enter a share from 1 to 100%.

Consumption (your number)

Wh/mi

Energy per distance. Your display or app may show it; 20 Wh/mi is only an example value. Enter a consumption above zero.

Arithmetic from your numbers. The range you get depends on consumption, and consumption depends on how you ride, where and on what bike.

Range at other consumption

The same battery and usable share at other consumption values. Doubling consumption halves the range.

What the inputs mean

Battery energy: in watt-hours (Wh), often printed on the battery. If the label gives volts and amp-hours instead, multiply them.
Usable share: how much of the rated energy you actually use before you stop. It is an assumption you set, not a property we know for your battery. The default is an example value.
Consumption: energy per distance, in Wh per mile or Wh per km. Some displays and apps show it; otherwise divide the Wh you used on a known ride by its distance.

The formula

battery (Wh) = voltage (V) × capacity (Ah)
range = battery (Wh) × usable share ÷ consumption (Wh per mile or km)
Wh/km = Wh/mi ÷ 1.609344

Worked example

A 36 V battery rated at 14 Ah holds 36 × 14 = 504 Wh. With an assumed 80% usable, that is 403.2 Wh. At 20 Wh/mi (12.4 Wh/km) the range is 403.2 ÷ 20 = 20.2 miles, or 32.4 km. At 15 Wh/mi the same battery gives 26.9 miles; at 30 Wh/mi, 13.4 miles.

What changes consumption

We do not give consumption figures, because they vary too much between bikes, riders and routes. The direction of each effect is plain physics:

Assist level: a higher level asks the motor for a larger share of the work, so consumption rises and range drops.
Your own power: every watt you pedal is a watt the battery does not supply. Pedaling harder at the same speed lowers consumption.
Hills: climbing lifts rider and bike, which takes energy. A hilly route uses more than a flat one of the same length.
Speed and wind: air drag rises steeply with speed, so riding faster or into wind raises consumption.
Weight: a heavier load adds rolling resistance and climbing work.

The cycling power calculator shows how many watts a speed, slope and wind take, which is the load the motor and your legs share. The best number to use here is your own, measured over a few typical rides.

Why rated Wh is not all usable

A battery rarely delivers every rated watt-hour in real use, and many riders stop before the display reaches zero. That is why the tool asks for a usable share instead of assuming 100%.

Questions

How do I calculate e-bike range?

Multiply battery watt-hours by the share you use, then divide by your consumption. 504 Wh × 80% ÷ 20 Wh/mi = 20.2 miles.

How do I convert volts and amp-hours to watt-hours?

Multiply them. A 36 V, 14 Ah battery is 504 Wh; a 48 V, 14 Ah battery is 672 Wh.

How far can a 500 Wh battery go?

It depends on your consumption. With 80% usable (400 Wh): 26.7 miles at 15 Wh/mi, 20 miles at 20 Wh/mi and 13.3 miles at 30 Wh/mi.

Does assist level change range?

Yes. A higher assist level makes the motor supply more of the power, so consumption goes up and range goes down. How much depends on the bike and how you ride, so measure your own consumption at each level.