Fuel Efficiency Basics: Organize Trip Miles and Gallons Clearly
A fuel efficiency worksheet is arithmetic on a fill-up interval you control: statute miles driven, US gallons used, and the fuel price you paid. This guide explains that logic in plain language. It is educational only—not an EPA window sticker, dyno test, fleet telematics report, or live pump-price feed.
What a Fuel Worksheet Actually Answers
The useful question is not 'What MPG does the manufacturer promise?' It is 'If these miles and gallons are right, what observed efficiency and fuel cost per mile appear?' A transparent worksheet makes that comparison visible. Real on-road results vary with speed, load, temperature, tire pressure, and blend quality that no single tank encodes. Treat every MPG figure as a trip scenario you still need to average across several fill-ups.
The Inputs That Drive the Math
Most educational fuel worksheets need miles driven for one interval, US gallons used to refill, and fuel price per US gallon. Keep one vehicle and one unit system. If your pump dispenses liters, convert to US gallons before entering so MPG and cost per mile stay consistent.
Trip Inputs and What They Do Not Prove
| Input | What it does here | What it does not prove | Common confusion |
|---|---|---|---|
| Miles driven | Seeds distance for MPG | Highway vs city split | Mixing odometer km without conversion |
| US gallons used | Seeds fuel volume for MPG | Tank capacity or residual fuel | Entering Imperial gallons as US gallons |
| Fuel price per gallon | Seeds cost per mile | A national average pump price | Using list price instead of what you paid |
| MPG result | Observed trip efficiency | EPA combined label compliance | Comparing one short tank to a sticker |
How the Worksheet Orders the Math
Compute miles per gallon
MPG = miles driven ÷ US gallons used.
Convert to metric consumption
L/100km = (100 × 3.785411784) ÷ (MPG × 1.609344).
Derive fuel cost per mile
Cost per mile = fuel price per gallon ÷ MPG.
Average several tanks
Repeat across fill-ups before comparing vehicles or commuting styles.
Keep non-fuel costs separate
Maintenance, insurance, and depreciation are outside this fuel-only model.
Run the Fuel Efficiency Worksheet
Enter miles, US gallons, and price per gallon for one fill-up interval:
Open Fuel Efficiency CalculatorWorked Scenario Without Claiming a Label
Suppose you drove 300 miles on 10 US gallons at $3.50 per gallon. MPG is 30. Liters per 100 km is about 7.84 using the NIST US-gallon and statute-mile relationships. Cost per mile is 3.50 ÷ 30 ≈ 0.1167. Change gallons to 15 and MPG falls to 20, raising cost per mile at the same price. The worksheet obeys your logs; it does not invent an EPA rating.
What This Model Intentionally Omits
- EPA, WLTP, or manufacturer sticker cycles
- Live fuel-price APIs and station rankings
- Imperial gallons without conversion
- Maintenance, insurance, tolls, and depreciation
- Guarantees about future trip economy
How to Gather Inputs Safely
Note the odometer at fill-up, drive normally, then refill and record gallons and price from the receipt. Prefer full-to-full intervals. Short partial tanks amplify pump cutoff noise. Convert liters to US gallons before entry, and label highway-only or city-only scenarios instead of blending them into one misleading average.
Bottom Line
Fuel efficiency basics are about transparent trip arithmetic: miles, US gallons, MPG, metric conversion, and fuel-only cost per mile. Keep language cautious, keep units consistent, and treat every result as a logged scenario—not a laboratory label.