Why is my real e-bike range worse than the maker's figure?

Quoted maximums assume minimum assist, flat ground, a light rider, no wind and a new battery, usually all at once. Your weight, your route and how hard you pedal matter more than which bike you bought.

How much e-bike range does cold weather cost?

Around 10 to 15 per cent near freezing and up to 30 per cent well below it. The energy is not gone, just unavailable while the pack is cold, so keeping the battery indoors until you set off recovers most of it.

Does a bigger e-bike motor use more battery?

Only if you use it. A 750 W motor ridden gently draws much the same as a 250 W one at the same speed. High assist and high speed drain a battery, not the rating on the motor.

E-Bike Range Calculator: Distance, Time and Wh per km

Q: How do I work out watt-hours from volts and amp-hours?

Multiply them. A 36 V 14 Ah battery is 36 times 14, which is 504 Wh.

Q: How long does an e-bike take to cover a distance?

Distance divided by average speed. Average speed is well below top speed once stops, junctions and hills are included: 18 to 22 km/h is typical for commuting even on a bike that assists to 25 km/h.

How far the battery goes, how long that takes, and whether the ride you are planning fits.

1

What are you riding?

2

Battery

Capacity

Wh

Printed on the battery, or volts × amp-hours.

3

Weight

Rider

kg

Bike

kg

Cargo

kg

4

The ride

Bike type

Assist level

Average speed

km/h

Terrain

Surface

Stops

5

Your range

You should get about

—km

Ride time: —
Consumption: —
Usable energy: —

Will I make it? Ride distance

km

Advanced: wind, temperature, battery health

Headwind

km/h

Temperature

°C

Battery health 100% Most packs hold about 80% after 500–1000 full cycles.

Battery you actually use 90% Few people ride to a flat battery. 90% is a fair default.

Drive efficiency 80% Motor and controller losses. Around 80% for a mid-drive, a little less for a hub.

What actually decides e-bike range

Range is battery energy divided by how fast you spend it. The battery half is easy — a 500 Wh pack holds 500 Wh. Everything interesting is in the other half.

How much of the work you do. The biggest lever by far, and the one most calculators ignore. In Eco the motor covers roughly a quarter of the effort; in Turbo it covers three quarters; on a throttle it covers all of it. That alone is a three-to-one swing in range on the same battery.

Speed, and then speed again. Air resistance rises with the cube of speed, so going from 20 to 30 km/h more than triples the drag power. This is why a 250 W European pedal-assist uses 3–6 Wh/km and a fat-tyre throttle bike at 32 km/h uses 15–20.

Weight and hills together. Weight barely matters on the flat and matters enormously uphill, because lifting mass is the one cost you cannot get back — you brake on the way down.

Cold. A lithium pack does not use more energy when cold, it holds less. At freezing you lose over 10% of capacity, and you get it back when it warms up.

Rough range by battery and assist level

Kilometres for a 100 kg total on a city e-bike, rolling terrain, 22 km/h. A sanity check only — the calculator adjusts for your own numbers, and terrain and speed move these a lot.

Battery	Eco	Tour	Sport	Turbo
400 Wh	80 km	50 km	36 km	30 km
500 Wh	100 km	63 km	45 km	38 km
625 Wh	125 km	78 km	56 km	47 km
750 Wh	150 km	94 km	68 km	56 km
1000 Wh	200 km	125 km	90 km	75 km

Multiply by 0.62 for miles. Mountainous terrain or a strong headwind can halve any of these.

Trek, Bosch, Specialized and the maker's own figures

Trek, Specialized, Giant and the rest all publish range tools, and most of them run on Bosch's or Shimano's numbers underneath. They are good, and worth using for your exact bike — they know its motor map and battery.

Two things to know when you compare them with this one. Their quoted maximums assume minimum assist, flat ground, a light rider and a new battery all at once, which is why the headline figure is often double what people get. And they cannot know your weight, your route or how hard you pedal, which between them matter more than the bike does.

This calculator is checked against Bosch's own range assistant: for an 800 Wh battery in Eco+ at 12 mph on a hilly route with a 220 lb total, Bosch gives 152 miles and this lands within about 4% of it.

Getting more out of a charge

In rough order of how much they are worth:

Drop an assist level and pedal harder. Worth more than everything else on this list combined.

Slow down. Three or four km/h off your average is a surprising amount of range, because drag goes with the cube of speed.

Check your tyre pressure. Soft tyres are pure loss — our tyre pressure calculator will get you to the right number.

Carry less, and keep the battery warm in winter. Bring it indoors before you leave rather than starting from a cold shed.

Anticipate. Every stop throws away the energy you just spent getting up to speed, and in town that is a real share of the total.

FAQs

How far will a 500 Wh e-bike go?

Roughly 40 km in Turbo on hills and up to 100 km in Eco on the flat, for an average rider and bike. The assist level you use decides most of it.

How do I work out watt-hours from volts and amp-hours?

Multiply them. A 36 V 14 Ah battery is 36 × 14 = 504 Wh. Switch the battery input to V × Ah above and it does it for you.

How long does an e-bike take to cover a distance?

Distance divided by your average speed — the calculator shows the ride time alongside the range. Average speed is well below top speed once stops, junctions and hills are in it: 18–22 km/h is typical for commuting even on a bike that assists to 25.

Why is my real range worse than the maker's figure?

Those figures assume minimum assist, flat ground, a light rider, no wind and a new battery, usually all together. Change any one and the number falls. Your weight, your route and how hard you pedal matter more than which bike you bought.

How much range does cold weather cost?

Around 10–15% near freezing and up to 30% well below it. The energy is not gone, just unavailable while cold — keep the battery indoors until you set off and you will get most of it back.

Does a bigger motor use more battery?

Only if you use it. A 750 W motor ridden gently draws much the same as a 250 W one at the same speed. What drains a battery is high assist and high speed, not the rating on the motor.

The code behind this calculator

A simplified, open-source version of this tool is on GitHub — the range model as readable, dependency-free code, with tests and a walk-through of how the sums work. Free to read, fork or build on. View the source on GitHub →