Fuel & Efficiency Calculator

Fuel Tank Range Calculator

Planning a long stretch between gas stations? See how far a full tank takes you — and how many miles are left in the tank you have right now.

Your Vehicle

E¼½¾F

Fuel you'd rather not run below. Subtracted from usable range.

Range on Current Fuel

225 mi

on 7.5 gal in the tank

Full-Tank Range

450 mi

Usable to Reserve

195 mi

Gallons to Fill

7.5 gal

Miles per Gallon Left

30 mi

Real-world note

Highway cruising can beat this range; city traffic, cold weather, and towing cut it. Keep a 30-mile buffer as insurance.

How it works.

Full-tank range = Tank size × MPG Current fuel = Tank size × (Level % ÷ 100) Range on current = Current fuel × MPG Usable to reserve = (Current fuel − Reserve) × MPG

Frequently asked questions.

How accurate is the fuel gauge for this?

Fuel gauges are approximate and often non-linear — the needle drops slowly at first, then faster near empty. Use the slider as an estimate and keep a safety buffer, especially below a quarter tank.

How far can I drive after the low-fuel light comes on?

Most cars have a reserve of roughly 1–3 gallons when the light appears, which is often 30–60 miles depending on MPG. It varies by model, so don't rely on it — treat the light as "fill up soon," not "keep going."

Why is my real range lower than this estimate?

The formula uses your entered MPG. City driving, cold starts, aggressive acceleration, roof racks, heavy loads, and towing all lower actual MPG, which shortens range. Use your real-world combined MPG for the best estimate.