Fuel Tank Range Calculator

Fuel tank range tells you how far your vehicle can travel on a full tank, and how far is left from whatever the gauge is reading now.

Core formulas: Maximum Range = Tank Capacity × Fuel Efficiency Current Range = Maximum Range × Current Tank Level %

Metric conversions: Range (km) = Tank Capacity (liters) × Fuel Efficiency (km/L) With L/100km instead: Range (km) = Tank Capacity ÷ (L/100km) × 100 Converting the two: MPG = 235.2 ÷ (L/100km)

For the cost of filling up, or the cost of a specific trip, use the Fuel Cost Calculator instead. This page deals only in distance.

Typical fuel tank sizes by vehicle class:

Worked example: A compact SUV with a 14 US gallon tank, averaging 32 MPG, gauge sitting at 25%.

Maximum range = 14 × 32 = 448 miles (721 km) Fuel on board = 14 × 25% = 3.5 gallons Current range = 3.5 × 32 = 112 miles (180 km)

Treat the last quarter tank as smaller than it looks. Fuel gauges are not linear, and most read optimistically in the top half and pessimistically near empty, because the float arm sweeps an irregularly shaped tank. The low-fuel light usually comes on with 1.5 to 3 gallons left, which is deliberately conservative. Running the tank to fumes also stirs up whatever sediment has settled at the bottom and pushes it into the fuel filter, and on older cars the in-tank pump relies on surrounding fuel to stay cool. Plan on refuelling at about 75% of the number above, which is what the result panel works out for you. That leaves you a quarter of a tank, which is enough to pass a station you do not like the look of and reach the next one. Our road trip stops and road trip time calculators use the same 75%, so a trip planned across the three pages holds together.

One more thing the arithmetic cannot know: the efficiency figure you enter is almost certainly a mixed or best-case number. A tank spent towing, or spent in city traffic in January, can come in 30% short of the range shown here.

This page or the remaining range one?

This page plans from the vehicle. Tank capacity out of the handbook, a gauge percentage, and it gives you the full-tank range, what is left now, and the mileage to start looking for a station. Open it before the drive.

The fuel range remaining calculator is the one for mid-journey. It takes the litres or gallons you actually have rather than a percentage, and it adjusts for how you are about to drive: highway 15% better than mixed, stop-start city 15% worse. That driving-style factor is the thing this page deliberately leaves out, since a tank-capacity figure has no business assuming what the next hundred miles look like.

Feed both the same fuel and the same economy and the distance matches: ten US gallons at 30 mpg is 300 miles either way.