Electric Vehicle Range Calculator
An electric vehicle's range is simply the energy it can use divided by the energy it spends per mile. Usable energy is the battery's nameplate capacity times the usable fraction times the current state of charge; efficiency is the kilowatt-hours used per mile. This calculator divides one by the other to give your range right now, plus the full-charge range and the usable energy in kilowatt-hours, all from figures you enter, so it reflects your vehicle and conditions rather than an idealised rating.
EV range formula
Usable energy (full) = capacity * usable fraction / 100
Usable energy now = usable energy (full) * state of charge / 100
Range now = usable energy now / efficiency
Full-charge range = usable energy (full) / efficiency
Miles per kWh = 1 / efficiency
Range is energy divided by energy per mile. The usable fraction trims the nameplate capacity to what the car will actually use, and the state of charge scales it to your current battery level.
Electric vehicle range context
- The US EPA rates EV range and efficiency at fueleconomy.gov using standard test cycles.
- Usable capacity is less than nameplate capacity because of protective buffers.
- Efficiency is often quoted as kWh per 100 miles; divide by 100 for kWh per mile.
- Cold weather, high speed and climate control raise consumption and cut range.
- Range scales directly with state of charge: half a battery gives roughly half the range.
EV range: frequently asked questions
How is EV range calculated?
Range equals the usable battery energy divided by the energy used per mile. Usable energy is the battery capacity in kilowatt-hours times the usable fraction times the current state of charge. Dividing by efficiency in kWh per mile gives miles. For a 60 kWh battery at 100 percent using 0.30 kWh per mile, range is about 200 miles.
Why use a usable-capacity fraction?
Manufacturers reserve a buffer at the top and bottom of the battery to protect its life, so the usable capacity is less than the nameplate capacity. A usable fraction of about 90 to 95 percent is common. Enter your vehicle's usable figure, or set it to 100 percent if you already entered usable kWh.
What efficiency should I use?
EV efficiency is energy per mile, often quoted as kWh per 100 miles. Divide that by 100 to get kWh per mile. The US EPA rates EVs at fueleconomy.gov. Cold weather, high speed and climate control all raise consumption, so enter the figure for your conditions.
How does state of charge affect range?
Range scales directly with state of charge. At 50 percent charge you get half the full range. The calculator multiplies usable capacity by your state of charge percentage, so you can see how far you can go right now, not just on a full battery.
Why is my real range lower than the rating?
EPA range figures use standardised test cycles. Real driving at highway speed, in cold weather, with heating or air conditioning, or with heavy loads uses more energy per mile, reducing range. Enter your real-world efficiency to get a range that matches your driving.
Official sources
- U.S. Department of Energy and EPA: Electric Vehicles.
- U.S. Department of Energy, Alternative Fuels Data Center: Electric Vehicle Basics.
Reviewed by the CalculatorHub team, edited by James Graham, 16 June 2026. See our methodology.