The range of electric bikes can vary, but most riders are able to achieve a 10-20 miles per charge on the average e-bike model. One of the main factors in determining how far you can travel on a single charge is how much assistance you provide. Rated by amp hours (AH), the typical e-bike battery has a capacity of 10-12AH. Without pedaling, riders can expect a range equal to this rating (i.e., 10AH = 10 miles). But since most riders will pedal along the way, the majority of e-bikes are rated up 15-30 miles per charge. Obviously, the more pedaling you do, the less strain on the battery and the more range you'll achieve. Keep in mind, 'pedal-assist' bikes have higher ratings and achieve more range than throttle-controlled bikes because the rider is required to pedal at all times.
Another factor that can have a big impact is terrain. If you live in a hilly area or have lots of steep inclines - expect less range from your e-bike. Larger riders or people carrying heavy loads can also expect reduced output. Because weight is a factor, this also means higher quality NiMH or Li-Ion batteries are capable of slightly longer ranges due to their reduced weight. Other factors include wind and road conditions.