EV Range Calculator Formula

Understand the math behind the ev range calculator. Each variable explained with a worked example.

Formulas Used

Estimated Range

estimated_range = usable_kwh * efficiency

Range (km)

range_km = usable_kwh * efficiency * 1.60934

Available Energy

kwh_available = usable_kwh

Variables

VariableDescriptionDefault
battery_kwhBattery Capacity(kWh)75
charge_levelCurrent Charge Level(%)90
efficiencyEfficiency(mi/kWh)3.5
usable_kwhDerived value= battery_kwh * charge_level / 100calculated

How It Works

How EV Range Is Calculated

Multiply the available battery energy by the vehicle's efficiency (miles per kWh).

Formula

Range = Battery kWh x Charge Level x Efficiency (mi/kWh)

Efficiency varies with speed, temperature, terrain, HVAC use, and driving style.

Worked Example

75 kWh battery at 90% charge, 3.5 mi/kWh efficiency.

battery_kwh = 75charge_level = 90efficiency = 3.5
  1. 01Usable energy = 75 x 90% = 67.5 kWh
  2. 02Estimated range = 67.5 x 3.5 = 236 miles
  3. 03In kilometers = 236 x 1.609 = 380 km

Frequently Asked Questions

What affects EV range?

Temperature (cold reduces range 20-40%), speed (highway uses more energy), HVAC use, terrain (hills), cargo weight, and driving style all affect range.

What is typical EV efficiency?

Most EVs achieve 2.5-4.0 mi/kWh. Smaller efficient cars reach 4+ mi/kWh, while large SUVs may get 2.0-2.5 mi/kWh.

Why does my actual range differ from the EPA rating?

EPA ratings are tested under controlled conditions. Real-world range varies with temperature, speed, accessories use, and individual driving habits.

Ready to run the numbers?

Open EV Range Calculator