Fuel Distance Calculator
How far will the fuel in your tank actually take you? Multiply what is in the tank by how far your car goes on each liter or gallon, and you have the answer. This fuel distance calculator does that arithmetic in metric or imperial units, and a second mode works backwards from a planned trip distance to the fuel you need.
Fuel Distance Calculator
Range from the fuel you have, or fuel needed for the trip ahead
How far can you go on the fuel in the tank?
Planning a trip? Enter the distance and find out how much fuel it takes.
Quick Answer
With 40 liters in the tank and 15 km per liter, you can drive 600.0 km (372.8 miles), and the tankful costs $60.00 at $1.50 per liter, or $10.00 per 100 km. Planning a 500 km trip at the same efficiency needs 33.33 liters, about $50.00. Treat both figures as maximums and keep a reserve, because real driving rarely matches a steady efficiency figure.
Key takeaways
- Range is fuel multiplied by efficiency, with units matched before you multiply.
- The same tool runs backwards: distance divided by efficiency gives the fuel a trip needs.
- Cost is always fuel used multiplied by the price per liter, so enter a per-liter price.
- Your dashboard average beats the brochure figure for planning a real trip.
How to use the two modes
The Trip range mode answers one question: how far can you go on the fuel you have. Enter the fuel in the tank, its unit, your efficiency, and the efficiency unit, then add an optional fuel price to see the trip cost and the cost per 100 km. The Fuel needed mode reverses it: enter a planned trip distance and the same efficiency figure, and it returns the fuel that trip takes plus its cost. Switching modes hides the previous result, so you always know which answer you are looking at. If you drive the same route every day, the commute expense calculator turns that daily distance into a monthly fuel bill.
The fuel distance formula, in plain units
Every mode here is one multiplication or division, once the units agree. Range equals fuel amount multiplied by fuel efficiency: liters with km per liter, or gallons with miles per gallon. A consumption figure in liters per 100 km converts first, because it runs the wrong way round for multiplying: km per liter equals 100 divided by the L per 100 km figure. Miles per gallon converts to km per liter by multiplying by 0.425144, the US-gallon conversion the tool uses. Cost is simpler still: fuel used multiplied by the price per liter. One point of honesty about the price field: the tool prices the liters it computes, so the price you enter must be per liter in both modes. If you only know a per-gallon price, divide it by 3.785 first, or the cost will come out nearly four times too high.
Worked examples you can check by hand
The prefilled values are the worked example, and every number below reproduces exactly when you press Calculate. Start with the range mode: 40 liters at 15 km per liter gives 40 multiplied by 15, which is 600.0 km, or 372.8 miles after dividing by 1.60934. At $1.50 per liter the tankful costs $60.00, and $60.00 divided by 600 km times 100 gives $10.00 per 100 km. Switch to imperial and the same shape holds: 10 gallons at 25 mpg gives 250 miles. With a consumption figure instead of an efficiency figure, 40 liters at 7.5 L per 100 km first converts to 13.33 km per liter, then gives 533.3 km. The reverse mode is one division: a 500 km trip at 15 km per liter needs 500 divided by 15, which is 33.33 liters (8.81 gallons), costing $50.00 at $1.50 per liter.
| Example | Inputs | Result |
|---|---|---|
| Range, metric | 40 L at 15 km/L, $1.50/L | 600.0 km (372.8 miles), $60.00 |
| Range, imperial | 10 gal at 25 mpg | 250 miles |
| Range, consumption figure | 40 L at 7.5 L/100 km | 533.3 km |
| Fuel needed | 500 km at 15 km/L, $1.50/L | 33.33 L (8.81 gal), $50.00 |
Why your real range is shorter than the calculator says
A calculator answer assumes one steady efficiency figure, and no real trip holds steady. Speed is the biggest lever: aerodynamic drag climbs steeply once you pass highway cruising speed, so the same car can return very different figures at 90 km per hour and at 130. Load, hills, headwinds, cold starts, and stop-and-go traffic all pull in the same direction, which is down. The official ratings on FuelEconomy.gov’s Find and Compare Cars pages come from laboratory test cycles, so they are a fair way to compare cars and a poor promise for any single tank. The practical habit is to plan your next fuel stop at around 90 percent of the calculated range and to treat the last few liters as unusable: gauges read optimistically near empty, and running a tank dry risks the fuel pump. If you want the most honest efficiency figure of all, measure it yourself over several tanks: liters filled divided by kilometers driven, times 100.
What competing fuel calculators miss
Most fuel distance tools do one thing: range from fuel and efficiency, sometimes with a cost line. The gap that matters on a real trip is the reverse question, how much fuel does this distance need, and almost none of them answer it as a working mode. One rival documents fuel needed in a paragraph of advice instead of letting you compute it. Another handles only miles per gallon and leaves metric drivers to convert by hand. A third gives range but no cost, so you still do the money math yourself. This page keeps both directions as real modes, accepts all three efficiency units directly, and shows cost per 100 km alongside the total, which is the figure that makes two cars or two fuel prices comparable at a glance. If you already know your miles per gallon and want the full economy picture, the mpg calculator covers consumption conversions in more depth, and the cost per trip calculator prices a journey that includes more than fuel alone.
Frequently Asked Questions
Multiply the fuel quantity by the efficiency, with the units matched first: 10 gallons at 25 mpg gives 250 miles, and 40 liters at 15 km per liter gives 600 km. The tool converts gallons, miles per gallon, and liters per 100 km into one consistent set of units before it multiplies, so mixed units cannot silently produce a wrong number.
Divide the trip distance by your efficiency. A 500 km trip at 15 km per liter needs 33.33 liters, which is 8.81 gallons and about $50.00 at $1.50 per liter. Use the Fuel needed mode for this: it does the division and the cost in one step.
Divide 235.214 by the mpg figure: 25 mpg equals 9.41 L per 100 km. The conversion runs inversely because miles per gallon is distance per unit of fuel while liters per 100 km is fuel per fixed distance. The tool accepts both units directly, so you rarely need to convert by hand.
Most gasoline cars fall between 20 and 30 mpg, about 8 to 12 L per 100 km. Hybrids do better, trucks and SUVs worse, and your own dashboard average over several tanks is more useful than any published figure for planning. Use the figure your car actually achieves on your kind of driving.
No. Efficiency varies with speed, load, terrain, and weather, and running a tank dry risks the fuel pump. Treat the result as a maximum and plan refueling with a comfortable reserve, roughly 10 percent of the calculated range, rather than aiming for the last kilometer.
Fuel used multiplied by the price per liter. For the range mode that is the whole tank; for the fuel needed mode it is the trip’s share. Enter a per-liter price in both modes: if you only know a per-gallon price, divide it by 3.785 first, because the tool prices liters.
Not directly: electric cars use kilowatt-hours per 100 km rather than liquid fuel, so none of these units apply. The math is analogous, range equals battery size divided by consumption, but this tool’s units are fuel based and its conversions assume gasoline or diesel volumes.
Because the formula multiplies them. Mixing gallons with km per liter silently produces a wrong number, which is why the tool converts everything internally before multiplying. If you enter efficiency in one unit system and fuel in another, pick the matching unit from each dropdown and the tool handles the rest.
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References
- U.S. Environmental Protection Agency and U.S. Department of Energy, Find and Compare Cars. Accessed October 25, 2026.
- U.S. Environmental Protection Agency and U.S. Department of Energy, Gas Mileage Tips. Accessed October 25, 2026.
- U.S. Environmental Protection Agency and U.S. Department of Energy, Gas Mileage Tips: Driving More Efficiently. Accessed October 25, 2026.
- U.S. Energy Information Administration, Gasoline and Diesel Fuel Update. Accessed October 25, 2026.
- U.S. Energy Information Administration, Gasoline Explained. Accessed October 25, 2026.
- U.S. Environmental Protection Agency, Green Vehicle Guide. Accessed October 25, 2026.
- U.S. Department of Energy, Alternative Fuels Data Center: Alternative Fuels and Advanced Vehicles. Accessed October 25, 2026.