What does eBike battery watt-hours mean?

Watt-hours (Wh) measure a battery's total energy capacity — it's the most useful number for comparing range across different batteries. A 500Wh battery has roughly twice the energy of a 250Wh battery. Most quality eBikes offer 400-750Wh; cargo and touring bikes may have 1,000Wh+. As a rough rule, expect 20-30 Wh of consumption per mile in mixed riding conditions.