Ebike Battery Pack Calculator

A simple, transparent estimate for your next ride. Runs entirely on this site, with no account or external calculator service.

THE BATTERY WORKBENCH

How much battery do you need?

Set your trip distance and energy use. See the capacity, reserve and equivalent amp-hours together.

Distance units Total trip distance kmInclude the return journey if you cannot charge at your destination. Assumed energy use Wh/kmUse your own measured consumption where available. The default is an editable example, not a tested bike rating. Battery reserve 20%The percentage of capacity you plan to leave unused. Battery voltage

YOUR CAPACITY ESTIMATE

563 Wh

11.7 Ah at 48 V

450 Wh for the trip

Trip energy: 450 WhRemaining area = reserve

This is the nominal capacity needed for your assumptions. Real range varies with hills, speed, load, weather, battery age and assistance.

THE MATH, OPENLY

30 km × 15 Wh/km ÷ 0.80 = 562.5 Wh

Put the result in perspective

Illustrative pack capacities compared with this estimate. This does not establish fit or compatibility with your bike.

For planning only. Match replacement batteries to the bike manufacturer's approved voltage, mounting, connectors and battery management system. Capacity alone does not establish compatibility or safety.

Head back to the calculator main page here.

The Math Behind the Calculator is fairly simple, using the following units and terms:

Battery Capacity Required (Wh) = Power Demand per distance traveled (Wh / mile or km) x Typical Distance Traveled (miles or km)

Watt-Hour (Wh) is a unit of energy used to describe the amount of power (watts) used in one hour. This number is an indication of the size of your battery and the subsequent range of your ebike.

Watt-Hour (Wh) = Amp-hours (Ah) x Volts (v)

Amp Hours (Ah) is the amount of current a battery can discharge over one hour.

Volts (V) the difference of potential that would drive one ampere of current against one ohm resistance. Typical Voltage in Electric Bike batteries is 36v, 48v, 52v, and 72v. These are typically multiples of 12 volts.

Some Other Calculator Options

Bosch has a pretty extensive range calculator where you are able to change all sorts of variables, from rider weight, terrain, type of bike, tires, etc. Understandably, this calculator is limited to the Bosch line of products but has some helpful information.

Grin Technologies has a very detailed simulator with the ability to add custom batteries and controllers and set a wide variety of vehicle parameters to see how factors such as throttle level, bike weight, hill grade affect the performance of an ebike.

Ready to Buy a new Battery Pack for your Ebike?

I’ve put together another post about the cost of a new ebike battery and below are a few options for ebike battery sources:

Amazon has a number of ebike batteries available, however, these are generally cheaper Chinese imports, so do your research and know that quality on these will often be less than the other options below
Luna Cycle has a large selection of high-quality ebike batteries (US-based)
Grin Technologies has a large selection of high-quality ebike batteries (Based in Canada)