Range always depends on usage and it's difficult to give exact range estimates. That being said, the mileage ranges we've listed assume a 350lb total system weight (our bikes range from 100-150lbs, plus rider) travelling at a constant 20mph (32kph) on level ground.
The following conditions will reduce your expected range, in decreasing order of importance:
1. Hilly terrain (although regen braking shines here)
2. Start and stop city riding
3. Cold weather or cold batteries
4. Headwinds or higher frontal surface area
5. Older batteries (expect 80% capacity after ~500 cycles)