How is ideal range calculated?

Ideal range is usable battery capacity in kWh multiplied by efficiency in distance per kWh. A 75 kWh pack at 3.5 mi/kWh gives about 263 miles before any real-world penalties are applied.

Why does cold weather cut range so much?

In cold weather the battery is less efficient, cabin heating draws several kilowatts, and tyre and air resistance rise. The combined effect commonly cuts usable range by around 20 percent, which is the penalty this tool applies when you tick cold weather.

Should I use the rated efficiency or my own?

Use your own lifetime efficiency from the trip computer for the most honest range. Manufacturer rated figures come from standardised test cycles that rarely match real driving, especially at highway speed or in extreme temperatures.

Why is charging slower above 80 percent?

To protect the cells, the battery management system tapers the charge rate as the pack fills, so the last 20 percent takes disproportionately long on a fast charger. The tool reduces the effective charge rate above 80 percent to reflect this taper.

What charger power should I enter?

A standard home outlet is about 1.4 kW (Level 1), a home wallbox is typically 7 to 11 kW (Level 2), and public DC fast chargers range from 50 kW to 350 kW. Enter the lower of the charger rating and your car's maximum accepted rate.

EV Range & Efficiency Calculator

Real EV range depends on far more than the headline figure on the window sticker. This calculator combines your usable battery and measured efficiency, then applies the penalties that actually erode range — cold, speed, climate control, and load — and estimates how long a charge will take.

How it works

Range and charging time are computed from straightforward energy relationships:

ideal range    = usable kWh × efficiency (distance per kWh)
adjusted range = ideal range × cold(0.80) × highway(0.85) × climate(0.92) × load(0.95)
charge time    = energy to add (kWh) / charger power (kW) / efficiency factor
energy to add  = capacity × (target% − start%) / 100

Only the multipliers you tick are applied, and the charging-efficiency factor drops above 80 percent state of charge to reflect the protective taper.

Example and notes

A 75 kWh pack at 3.5 mi/kWh gives about 263 miles ideal. Tick cold weather and highway speed and that falls to roughly 179 miles — a 32 percent reduction. Charging that same car from 20 to 80 percent on an 11 kW wallbox moves about 45 kWh and takes a little over four and a half hours. For accuracy, feed in your own lifetime efficiency rather than the rated figure, and remember that DC fast charging past 80 percent is rarely worth the time on a road trip.