EV Range Calculator
Estimate how far an electric car goes on one charge from battery capacity and consumption.
What this tool does
EV range is the usable battery capacity divided by the car's energy consumption. Enter the usable capacity in kWh and the consumption in kWh/100km (or miles per kWh), and the calculator returns the expected range in kilometres and miles. A reserve percentage accounts for the battery you should not use, and a weather or highway adjustment shows what to expect in harder conditions.
Estimates driving range from usable battery capacity and average energy consumption.
Accepts consumption as kWh/100km, km/kWh or miles per kWh, so any published figure works.
Shows range in both kilometres and miles, plus the consumption in every common unit.
Applies a reserve and a cold-weather or highway derating percentage so the estimate stays realistic.
How to use it
- Enter the battery capacity and say whether it is usable or total (gross).
- Enter the energy consumption in the unit your car or review quotes.
- Set a reserve percentage you want left at the end of a journey.
- Add an adjustment for cold weather or sustained highway speeds.
- Read the estimated range in kilometres and miles.
Why use this calculator
Published EV range figures come from laboratory cycles that assume mild temperatures, moderate speeds and no heating or cooling, so they flatter almost every car. This calculator starts from the two numbers that actually decide range - how much energy you can really use and how quickly the car spends it - and lets you derate them for a motorway run or a cold morning, which turns a brochure figure into one you can plan around.
Why we built it
We built the EV range calculator to accept usable and total battery capacity separately, because the difference between the two is exactly the margin a driver should not plan to use. The ev charging cost calculator turns the same consumption figure into a cost per charge, and the petrol vs electric calculator compares a year of electric driving with a year of petrol.
For the petrol side of the garage, the car fuel consumption calculator measures consumption, and the cost per kilometre calculator puts both powertrains on one cost per kilometre.
Who this tool is for
- Prospective EV buyers checking whether a model fits their driving
- EV drivers planning a trip with charging stops along the way
- Fleets estimating real-world range for assigned vehicles
- Anyone comparing an EV's efficiency with a petrol car's
When to use it
- Before a long trip, to see how often you will need to charge.
- When comparing two electric cars with different battery sizes.
- In winter, to work out the range you will really have.
- Before buying, to check the usable capacity behind the headline kWh.
How it is calculated
Range (km) = usable battery in kWh ÷ consumption in kWh/100km × 100. Range (miles) = usable kWh ÷ consumption in kWh/mile, or convert with 1 mile = 1.60934 km. If you only have total (gross) capacity, multiply by the usable percentage first - most cars let you use roughly 90% to 95% of the pack's nominal energy to protect battery life.
Worked example: a 60 kWh battery at 90% usable gives 54 kWh. At 17 kWh/100km, range = 54 ÷ 17 × 100 = 318 km, which is about 197 miles. Reserve 10% for battery health and you can plan on 286 km (177 miles).
Consumption is the whole story. The same 54 kWh at 22 kWh/100km on a winter motorway gives 245 km instead of 318 km - a 23% cut from conditions alone.
A worked example
These are the values the calculator opens with, so you can see exactly what it does with them. Change any value on the page and the result updates; the figures below come from the same calculation.
| Input | Value |
|---|---|
| Battery capacity | 60 kWh (total) |
| Usable percentage | 90% |
| Consumption | 17 kWh per 100 km |
| Reserve | 10% |
| Cold weather adjustment | 15% |
With those inputs, the calculator returns:
- Usable energy: 54.0 kWh
- Range, mild conditions: 318 km (198 miles)
- Range with a 10% reserve: 286 km (178 miles)
- Range in cold weather at 15% derating: 243 km (151 miles)
- Consumption: 17 kWh/100km, 5.9 km/kWh, 3.7 miles/kWh
What changes electric car range
Speed dominates: aerodynamic drag rises with the square of speed, so sustained motorway driving can use 20% to 30% more energy than the same distance at town speeds. Temperature matters next - cold batteries are less efficient, cabin heating draws real power, and a heat pump helps. Then come elevation, headwinds, payload, roof boxes, under-inflated tyres and a heavy right foot.
| Condition | Effect on range |
|---|---|
| Cold weather below 0°C | 10% to 30% lower |
| Sustained motorway at 120 km/h | 15% to 30% lower |
| Cabin heating on a cold day | 10% to 20% lower |
| Town driving with regenerative braking | 5% to 15% higher |
| Roof box fitted | 5% to 15% lower |
| Tyres at the correct pressure | Around 3% better than under-inflated |
What you enter, and what you get back
| Item | Details |
|---|---|
| Battery capacity | Usable or total kWh - the calculator applies the usable percentage. |
| Consumption | kWh/100km, km/kWh or miles/kWh. |
| Reserve | A percentage to leave unused, typically 5% to 10%. |
| Conditions adjustment | Optional derating for cold or highway driving. |
| Result | Range in km and miles, plus consumption in all common units. |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| Range much lower than the brochure | Official cycles assume mild conditions. | Enter real consumption from the car's own trip data. |
| Figure ignores part of the battery | Gross capacity entered as usable. | Set the usable percentage - usually 90% to 95%. |
| Winter range collapses | Cold pack plus cabin heating. | Apply a 15% to 25% derating in cold months. |
| Consumption unit mismatched | kWh/100km read as km/kWh. | Check which direction the unit counts. |
Assumptions and limitations
- Assumes a constant consumption figure; real driving varies leg by leg.
- Published battery capacity may be usable or gross - the calculator lets you state which.
- Weather and road adjustment percentages are typical values, not measurements of your car.
- Battery capacity fades with age, so an older car will give less range than the same calculation on day one.
Frequently asked questions
How far can an electric car go on one charge?
Most modern electric cars cover 250 to 450 km in real-world driving, with long-range models exceeding 500 km. The exact figure comes from usable battery capacity divided by consumption: 54 usable kWh at 17 kWh/100km gives 318 km. Winter motorway driving can cut that by a quarter, so plan on the derated number.
How do I calculate EV range?
Divide the usable battery capacity in kWh by the consumption in kWh/100km, then multiply by 100. A 60 kWh pack with 54 kWh usable at 17 kWh/100km gives 54 ÷ 17 × 100 = 318 km. For miles, convert the distance (1 km = 0.621 miles) or use consumption in kWh per mile.
What affects electric car range?
Speed, temperature, heating and cooling, elevation, headwinds, payload, tyre pressure, driving style and battery age. Aerodynamic drag rises with the square of speed, so highway cruising is the biggest single drain, while cold weather and cabin heating come close behind in winter.
How does cold weather affect EV range?
Expect 10% to 30% less range below about 5°C, and more near or below freezing. A cold battery accepts and delivers energy less efficiently, and cabin heating draws from the same pack - preheating while still plugged in, or using a heat pump where fitted, recovers much of that loss.
What is usable battery capacity?
It is the portion of the battery's energy the car actually lets you use, typically 90% to 95% of the nominal pack. Manufacturers reserve a buffer at both ends to slow degradation and to keep the car drivable when it reports empty. Always plan trips on usable capacity, not the headline kWh figure.
How do I improve my EV range?
Drive smoothly and at moderate speeds, use regenerative braking, keep tyres at the recommended pressure, remove roof boxes, and preheat or precool the cabin while the car is still plugged in. In cold weather, short frequent trips and a heat pump where available make the largest difference.