Range per Tank

Free Range per Tank calculator with clear step-by-step results.

About Range per Tank

Theoretical range assumes you run the tank dry, which nobody does. Deducting the reserve you will not touch gives practical range, and the load penalty accounts for the fact that a fully loaded or towing vehicle can consume 10-30% more than its quoted figure.

Formulas

Effective consumption

L/100km = quoted consumption x (1 + load penalty)

Practical range

km = (tank capacity - reserve) / effective consumption x 100

Worked example

With the default values below, Range per Tank returns Practical range before refuelling of 683.6. Change any input above and every figure here is recalculated in your browser.

Inputs used

Usable tank capacityminimum 0.5 L: 55 L
Fuel consumptionminimum 0.1 L/100km: 6.4 L/100km
Reserve you refuse to useminimum 0 L: 6 L
Consumption penalty for load or towingaccepts 0–100 %: 12 %

Results

Practical range before refuelling: 683.6 km
Range on a completely full tank: 767.3 km
Range held in reserve: 83.7 km
Consumption after the load penalty: 7.17 L/100km

Step by step

1Values used
2Effective consumption
3Practical range
4Practical range before refuelling= 683.6 km
5Range on a completely full tank= 767.3 km
6Range held in reserve= 83.7 km
7Consumption after the load penalty= 7.17 L/100km

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How much reserve should I keep?

Enough to reach the next station comfortably - often 10-15% of tank capacity. Running very low also risks drawing sediment and, on some vehicles, overheating an in-tank fuel pump.

Why is towing so costly in fuel?

Aerodynamic drag rises with frontal area and rolling resistance with mass. A caravan can easily add 30-50% to consumption, far more than the load penalty needed for a full car.