Truck MPG Calculator
Calculate semi truck miles per gallon from a fuel-up.
MPG = miles driven ÷ gallons used. Average U.S. Class 8 dry van: 6.0–7.0 MPG in 2026.
How it works
- 1Fill the tank completely
Reset the trip odometer at a known-full tank.
- 2Drive a normal route
Mixed highway/secondary gives the most realistic MPG for cost-per-mile use.
- 3Refill and divide
Miles ÷ gallons added at the next full = true MPG.
Example: 650 mi on 100 gal
| MPG | 6.50 |
| Annual fuel at 110k mi | ~16,923 gal |
| Annual fuel cost at $3.80/gal | ~$64,308 |
Takeaway: Push MPG to 7.0 and the same 110k miles costs ~$59,714 — $4,594/yr saved.
Key takeaways
- 6.5–7.5 MPG is good for a Class 8 dry van.
- Reefers average 5.8–6.5 MPG; heavy-haul 4.5–6.0.
- Slowing from 68 to 62 mph improves MPG by ~0.6.
Expert tips from Bonafide dispatchers
- 1
Inflate all 18 tires within 3 PSI of spec weekly — under-inflation costs ~0.2 MPG.
- 2
Cut idle to under 25% with a bunk APU.
- 3
Run tractor and trailer aero kits — combined gain is 4–7%.
Frequently asked questions
What is good MPG for a semi truck?+
6.5–7.5 MPG is good for a Class 8 dry van. Reefers average 5.8–6.5. Heavy-haul and tankers run 4.5–6.0.
How can I improve semi truck MPG?+
Slow to 62 mph, hold steady throttle, install aero skirts and tractor mud flaps, and keep all 18 tires within 5 PSI of spec.
Last reviewed June 15, 2026 by the Bonafide Trucking Solutions dispatch team.