EV efficiency & consumption calculator
Convert any EV efficiency unit via Wh/km, read the arithmetic, then price a trip from electricity cost and optional battery size.
Defaults to your region. Switch to compare any other scale.
Result
117.968 MPGe
mi/kWh → MPGe
3.5 mi/kWh → 177.535 Wh/km → 117.968 MPGe
- Canonical Wh/km177.535 Wh/km
- How calculated3.5 mi/kWh → 177.535 Wh/km → 117.968 MPGe
- Cost per 100 km2.8406
- Cost per 100 mi4.5714
- Cost per km0.0284
- Cost per mi0.0457
- Converted result117.968 MPGe
Via Wh/km + EPA MPGe
Standards: NIST mile (1 mi = 1.609344 km); EPA 1 US gal GE = 33.705 kWh. 3.5 mi/kWh → 177.535 Wh/km → 117.968 MPGe
All efficiency units
| Unit | Symbol | Value |
|---|---|---|
| km/kWh | km/kWh | 5.6327 |
| mi/kWh | mi/kWh | 3.5 |
| kWh/100 km | kWh/100 km | 17.753 |
| kWh/100 mi | kWh/100 mi | 28.571 |
| Wh/km | Wh/km | 177.535 |
| Wh/mi | Wh/mi | 285.714 |
| MPGe (US EPA) | MPGe | 117.968 |
About this tool
Electric vehicles report efficiency in opposite ways: distance per energy (km/kWh, mi/kWh, MPGe) or energy per distance (kWh/100 km, Wh/km). This tool converts through a canonical Wh/km value so every unit stays consistent.
kWh/100 km = 100 ÷ (km/kWh). MPGe follows the US EPA definition: one US gallon of gasoline equals 33.705 kWh, so MPGe = 33.705 × mi/kWh. The international mile is exactly 1.609344 km (NIST).
With a price per kWh you also get cost per 100 km / 100 mi, trip energy, trip cost, and estimated range from usable battery capacity. Winter, speed and cabin heat often raise real-world Wh/km — treat sticker figures as a baseline. Pair with the fuel cost calculator to compare petrol vs electricity per distance.
Formula
Canonical: Wh/kmkWh/100 km = 100 ÷ (km/kWh) = Wh/km ÷ 10km/kWh = 1000 ÷ Wh/kmMPGe = 33.705 × mi/kWh (EPA; 1 US gal GE = 33.705 kWh)1 mi = 1.609344 km (NIST)Trip kWh = distance_km × Wh/km ÷ 1000Cost / 100 km = (Wh/km ÷ 10) × price_per_kWh
How it is calculated
- Enter an efficiency value and choose From / To units (or open Trip cost mode).
- Convert to Wh/km, then to the target unit — inverse units use reciprocals (e.g. km/kWh = 1000 ÷ Wh/km).
- Read the step rows for the exact arithmetic of this input.
- Optionally set electricity price, trip distance and battery to see cost and range.
- Open the all-units table to compare every efficiency measure at once.
Questions
What is a good kWh/100 km for an EV?
Many modern EVs land roughly in the 12–20 kWh/100 km band in mild weather; large SUVs and cold winters often sit higher. Compare like-for-like (same speed, temperature, load).
What does MPGe mean?
Miles per gallon equivalent. The US EPA sets 1 US gallon of gasoline = 33.705 kWh, so MPGe = 33.705 × mi/kWh. It lets you compare EVs with petrol cars on one scale.
Why does winter lower EV efficiency?
Cabin heat draws from the battery, cold batteries accept charge and deliver power less efficiently, and denser air plus winter tyres add drag. Heat pumps help but do not erase the gap.
EV vs petrol — cost per 100 km?
For an EV: cost/100 km = (kWh/100 km) × price per kWh. For petrol use the fuel cost calculator: (L/100 km) × price per litre. Home overnight rates are usually far cheaper than pump prices; public DC fast charging can close the gap.
Are the results official advice?
No. Calculate This is an educational tool. For important decisions, check primary sources or ask a qualified professional.