EV range calculator

Enter capacity in kilowatt-hours, choose how efficiency is stated — kilowatt-hours per one hundred kilometers, watt-hours per kilometer, watt-hours per mile, kilometers per kilowatt-hour, or miles per kilowatt-hour — optionally set how much of the pack is usable, and the engine returns range_km, range_mi, usable_kwh, and a short formula tag for audits. Zero or negative efficiency is rejected with invalid_input because a non-positive efficiency does not define a meaningful distance per unit of energy.

What EV driving range means and what the response contains

Electric-vehicle range answers a single practical question: given how much energy the pack can deliver and how many units of energy the car spends per unit of distance, how far can you drive before the usable charge is gone. Drivers, fleet planners, and travel apps need that number before choosing a route, comparing two cars on the same highway loop, or deciding whether a partial charge is enough for the next leg. This calculator does not invent efficiency from weather, elevation, or speed; it trusts the efficiency value you supply and applies the matching closed-form identity for the selected unit system. The response echoes the normalized capacity_kwh, usable_pct, usable_kwh, efficiency and efficiency_unit, range_km and range_mi, the precision used, a method tag ev_range, and a compact formula string describing the path taken. There is no approximate Monte Carlo path and no live traffic or temperature feed: the engine either builds a finite range inside the supported numeric range or rejects the input with invalid_input. Rejected cases include missing capacity or efficiency, non-finite values, magnitudes above the documented ceiling, non-positive pack capacity, usable_pct outside zero to one hundred, and any efficiency that is zero or negative, because dividing by zero efficiency or scaling with a negative burn rate is not a valid trip plan. If you need charge time or energy cost, multiply or divide outside this tool; if you need remaining range from a partial state of charge, set usable_pct to the remaining percent of the pack. This page stays focused on the range identity so worksheets, APIs, and browser demos share one stable contract without inventing drivetrain physics.

How capacity, efficiency, and usable charge are read and stay consistent

Optional leading plus signs and scientific notation on numeric strings are allowed when they parse as finite decimals; embedded spaces, hex prefixes, and non-numeric tokens are rejected with a clear message so a bad cell does not become a wrong range estimate. The preferred fields are capacity_kwh for the nominal pack size in kilowatt-hours and efficiency for the energy-efficiency figure, but aliases such as capacity, battery_kwh, pack_kwh, energy_efficiency, consumption, and economy are accepted so spreadsheets, query strings, and typed forms can reuse the same contract. efficiency_unit selects the interpretation: kwh_per_100km is the default metric consumption rate familiar from sticker comparisons, wh_per_km and wh_per_mi are the dashboard-style watt-hour rates common on trip computers, and km_per_kwh or mi_per_kwh are the reciprocal efficiency figures used when a car advertises distance per kilowatt-hour. usable_pct defaults to one hundred when omitted and may be set anywhere from zero to one hundred to model a battery buffer, a manufacturer usable window, or a partial charge before departure. After validation the engine computes usable_kwh, applies the matching formula, and always reports both kilometers and miles using the exact international mile constant so dual-unit readers do not re-convert by hand. An optional precision field, with aliases decimals and dp, chooses how many decimal places to expose, defaulting to four and capped at fifteen so JSON goldens stay stable. Pair the free browser run on this page with the priced API when you need the identical mathematical result inside an automated pipeline without re-implementing Wh and kWh scaling yourself.

Where EV range checks fit in planning, fleets, and software

On this page the work runs entirely in your browser; through the API each successful lookup costs $0.002, failed validation is not charged, and nothing is stored after the response returns. That split — free interactive exploration and a priced, identical API — matches the rest of the KIT tier-A catalog and lets you move from a dashboard demo to an automated pipeline without changing the mathematical result.