E-Bike Range Calculator
A 36 V 14 Ah e-bike battery holds 36 × 14 = 504 Wh. With 85% usable (428.4 Wh) at 10 Wh/km the range is 428.4 / 10 = 42.8 km (26.6 mi).
How to use
- Enter the battery voltage and amp-hours from the battery label (for example 36 V 14 Ah). If the label shows only watt-hours, divide them by the voltage to get amp-hours.
- Keep usable capacity at 85% unless you know your battery: the battery management system and voltage cut-off leave some energy unused, and older batteries hold less.
- Pick assist level, terrain and rider weight to fill in the average consumption, or overwrite it with the Wh/km your display shows after a few rides.
How it works
Battery energy (Wh) = voltage (V) × capacity (Ah). Example: 36 V × 14 Ah = 504 Wh.
Usable energy = Wh × usable %. Range (km) = usable Wh / consumption (Wh/km). 504 × 0.85 / 10 = 42.8 km (26.6 mi).
Consumption presets for a 75 kg rider on flat paved roads: eco 6, tour 9, sport 13, turbo 18 Wh/km. Rolling terrain multiplies by 1.25 and hilly by 1.6. Each 10 kg above or below 75 kg changes consumption by 5%.
These presets are rules of thumb, not a standard. They sit inside the ranges that e-bike makers give in their range guides and that riders report from their displays. Wind, tyre pressure, stop-and-go riding, cold weather and cadence can move the result a lot.
Range by assist level
36 V 14 Ah battery (504 Wh), 85% usable, 75 kg rider, flat roads.
| Assist level | Wh/km | Range | Range (mi) |
|---|---|---|---|
| Eco | 6 | 71 km | 44 mi |
| Tour | 9 | 48 km | 30 mi |
| Sport | 13 | 33 km | 20 mi |
| Turbo | 18 | 24 km | 15 mi |
Common battery sizes
- 36 V 10 Ah = 360 Wh
- 36 V 14 Ah = 504 Wh
- 48 V 13 Ah = 624 Wh
- 36 V 20.1 Ah = 725 Wh
- 48 V 17.5 Ah = 840 Wh
Wh/km and Wh/mile
1 Wh/km = 1.609 Wh/mi. A figure of 10 Wh/km equals about 16 Wh/mi. To convert other battery units, see the Wh to Ah converter.
FAQ
How far does a 500 Wh e-bike battery go?
Roughly 40 to 70 km (25 to 45 miles) for most riders. With 85% usable energy and 10 Wh/km it is about 43 km; in eco mode at 6 Wh/km about 70 km.
How do I get watt-hours from volts and amp-hours?
Multiply them: 36 V × 14 Ah = 504 Wh, 48 V × 17.5 Ah = 840 Wh. Use the nominal voltage on the label, not the full-charge voltage.
Why is usable capacity below 100%?
The controller cuts power before the cells are fully empty to protect them, and capacity fades with age and in the cold. 80% to 90% of the label value is a common working figure.
What uses the most range?
High assist levels, hills, headwind, heavy loads, low tyre pressure and frequent starts. Riding in a lower assist level and pedalling at a steady cadence stretches the range most.
How can I measure my own consumption?
Charge fully, ride a known distance and read the energy used from the display or the charger. Wh used / km ridden is your Wh/km. Enter it in the consumption field.