How to use this calculator
- Enter route distance. Use the full trip distance, including return or deadhead miles if relevant.
- Enter measured MPG. Use loaded route fuel economy, not just a brochure number.
- Enter schedule. Set vehicles, trips per day and operating days for the planning period.
- Add idle fuel. Include engine-on idle time and idle burn rate if it matters for the route.
How it works
Moving-route fuel is distance divided by loaded fuel economy:
route_gal = route_miles / mpg
Idle fuel is added separately:
idle_gal = idle_hours x idle_gal_per_hour
Fleet totals multiply fuel per trip by the schedule:
period_fuel = fuel_per_trip x vehicles x trips_per_day x operating_days
period_cost = period_fuel_gal x price_per_gal
Worked example
Verified against the live calculator
A 120 mi route at 8 mpg uses 15 gal
while moving. Add 30 min idling at 0.8 gal/h and
the trip uses 15.4 gal. With 12 vehicles,
22 operating days and $4.25/gal fuel, the period
fuel cost is about $17,279.
Frequently asked questions
How do you calculate fleet fuel cost?
Route fuel is route distance divided by loaded MPG. Idle fuel is idle time times idle burn rate. The calculator adds both, then multiplies by vehicles, trips per vehicle per day, operating days and fuel price.
Should I use rated MPG or measured MPG?
Use measured loaded route MPG if you have it. Rated MPG usually misses payload, stop frequency, terrain, weather, driver behavior and auxiliary loads.
Does this include deadhead miles?
Only if you include them in route distance. Enter the complete cycle distance if the vehicle returns empty, repositions or runs non-revenue miles.
Is cost per mile based on moving miles only?
It divides total period fuel cost by the entered route distance times trips and vehicles. Idle fuel is included in cost, so cost per mile rises when idle time is high.
Method & assumptions
- Uses entered loaded MPG directly; no drive-cycle or terrain model is included.
- Idle fuel is a simple burn-rate times idle-time allowance.
- Does not include maintenance, tires, depreciation, insurance, tolls, labor, charging, taxes, payload changes, weather, dispatch variability or deadhead miles unless entered in route distance.
- Use vehicle speed, engine RPM and road-load horsepower for adjacent vehicle setup checks.