Gas Mileage (MPG) Calculator

For US cars and SUVs in 2026: 30+ combined MPG is good, 40+ is excellent, 50+ is hybrid territory. Pickups and large SUVs typically average 18–22 combined. EVs measured in MPGe routinely exceed 100. The EPA's combined number weights 55% city + 45% highway; your personal mix may differ substantially.

City driving wastes energy on acceleration, braking, and idling. Highway driving holds a steady speed where the engine operates near its efficiency peak. The penalty above ~55 mph is aerodynamic drag, which rises with the square of speed — that's why 65 mph beats 75 mph for fuel economy. Hybrids reverse this pattern (higher city MPG) because regenerative braking captures the energy normally lost in stops.

Five highest-leverage habits: (1) Keep tires properly inflated — under-inflation costs 1–3 MPG. (2) Drive smoothly — avoid hard acceleration and braking. (3) Hold steady speeds on the highway; cruise control helps. (4) Remove roof racks and unnecessary weight when not in use. (5) Combine errands into one trip — cold engines use much more fuel for the first 5 miles.

Rough math at typical 2026 prices: gas car at 30 MPG and $3.50/gal costs about $0.12/mile in fuel. EV at 3 mi/kWh and $0.16/kWh costs about $0.05/mile in electricity — under half. Public DC fast charging is more expensive (often $0.40–0.50/kWh) and brings cost closer to gas. Home Level 2 charging is the budget unlock for EVs.

Yes — typically 5–10% in city driving and less at highway speeds. The compressor draws 2–4 horsepower; the engine has to compensate. Rolling windows down trades AC for aerodynamic drag — on the highway, AC is usually more efficient than open windows. In stop-and-go traffic, windows down wins.