Heavy Vehicles
Truck MPG Calculator
The truck miles per gallon calculator works out fuel economy and running cost for pickups and big rigs alike. Trucks burn far more fuel per mile than cars, so even a small change in MPG translates into large dollar swings over a route or a year — which makes measuring it well worth the effort.
As a semi truck miles per gallon calculator, this tool takes your miles, the fuel used (US or UK gallons), and an optional diesel price, then returns MPG, cost per mile, total fuel cost, and CO₂ per mile (diesel emits about 22.4 lbs of CO₂ per US gallon). A load-type selector lets you note whether the run was empty, half, or full so you can interpret the result in context.
Semi-trucks (18-wheelers) average 5–8 MPG on highway at full load. Pickup trucks range from 14–22 MPG depending on engine and payload. Load weight is the single biggest factor — a fully loaded semi burns significantly more fuel per mile than an empty one running back to the depot. For full trip budgeting see our Trip Cost and MPG Cost calculators.
How to Use
- Enter the miles driven.
- Choose US or UK gallons and enter the fuel used.
- Select the load type for context.
- Optionally add the diesel price.
- Click Calculate Truck MPG (or press Enter).
Related tools: MPG Calculator, RV MPG Calculator, Boat MPG Calculator, MPG Cost Calculator.
Got Questions?
Truck MPG Calculator FAQ
A modern semi-truck (18-wheeler) averages 5.5–8 MPG on highway depending on load, speed, aerodynamics, and engine. Fuel-efficient trucks with idle-reduction technology can push above 8 MPG.
A full-size pickup truck (F-150, Ram 1500, Silverado) averages 16–24 MPG combined depending on engine. The V6 EcoBoost F-150 achieves around 20 MPG combined. Diesel pickups often do better.
At 6 MPG, a semi uses 0.167 gallons per mile. At $4.00/gal diesel, that’s about $0.67 per mile in fuel alone — not counting driver, maintenance, and tyre costs.
For pickups: remove tonneau cover weight, avoid aggressive acceleration, maintain tyre pressure, and use the smallest engine for your needs. For semi-trucks: reduce idle time, optimise speed (55–60 mph is most efficient), and use aerodynamic fairings.
Significantly. A fully loaded semi can use 30–40% more fuel per mile than an empty run. For pickups, carrying 1,000 lbs of payload typically reduces MPG by 1–2 miles per gallon.