E-bike range calculator
How far a battery really goes depends on who's riding, how hard the motor works and where. Put in the battery's watt-hours, or pick a model, and set the ride. The estimate updates as you go, with the brand's own claim beside it for comparison.
Estimated range
— miles
- Motor use
- — Wh per mile
- Usable battery
- — Wh
- Ride time
- —
- Charge cost
- —
An estimate, not a promise: two riders on the same bike can differ by half. The assumptions are below, and every one is adjustable.
How it works
What the calculator assumes
- Usable battery is 90% of the rating. Controllers cut out before the cells are empty, and a battery loses a little capacity every year. Cold weather takes another 20% for the ride.
- Moving a bike and rider costs 9 Wh per mile plus 0.05 × speed². That's rolling resistance, drivetrain and motor losses and air drag for a 60 lb bike with a 180 lb rider sitting upright: about 20 Wh a mile at 15 mph and 29 at 20 mph, whoever supplies it.
- The assist level sets the motor's share. Low assist has the motor supplying about 45% of that energy, medium 65%, high 80%. Throttle-only means the motor supplies all of it.
- Weight adds about 1% per 10 lb over 180 lb of rider and cargo, hills add 20 to 50%, a headwind 30% and fat tyres 15%.
- The brand's claim shown for a model is its published "up to" figure. Across the 174 e-bikes we list that publish both a battery size and a range, those claims work out to a median of 10.4 Wh per mile: low assist at a gentle pace on flat ground, with a light rider.
If range is what you're buying for, compare batteries rather than claims: our long-range e-bike ranking sorts by watt-hours, and every model page shows the battery size next to the brand's claim.
Questions
Common questions
- How far can an electric bike go on one charge?
- Most e-bikes go 20 to 50 miles on a charge in normal use. A typical 706 Wh battery gives about 25 miles at high assist or 45 at low assist on flat ground; hills, a heavy rider, headwinds and throttle-only riding cut that by a third or more.
- How do you calculate e-bike range?
- Divide the battery's usable watt-hours by the watt-hours the motor uses per mile. A battery's usable capacity is about 90% of its rating. Motor use runs from 9 to 11 Wh per mile at low assist on flat ground to 25 to 35 Wh per mile on throttle alone at 20 mph, more uphill.
- Why is my real range less than the brand claims?
- Brands test at the lowest assist level, on flat ground, with a light rider and no wind. Across the 174 e-bikes we list that publish both a battery size and a range claim, the "up to" figure works out to a median of 10.4 Wh per mile, which is eco assist at 12 to 15 mph. Ride at high assist and you'll use two to three times that.
- How many watt-hours does an e-bike use per mile?
- Roughly 10 Wh per mile at low assist, 15 to 20 at medium, 20 to 25 at high assist and 25 to 35 on throttle alone at 20 mph. Add 20 to 50% for hills, 30% for a headwind, 15% for fat tyres and about 1% for every 10 lb of rider and cargo over 180 lb.
- Does a bigger battery always mean more range?
- For the same bike and rider, yes, in proportion: 1,000 Wh goes twice as far as 500 Wh. Between different bikes it doesn't, because motor type, tyre width, speed and weight change the watt-hours per mile. That's why we rank long-range bikes by battery size, not by the brands' mileage claims.