Trip Fuel Cost Calculator
Miles, MPG, price — that's the whole equation. The diesel price below is this week's real U.S. average, not a stale number from 2023.
How this is calculated
gallons = miles ÷ MPG
fuel cost = gallons × price per gallon
Price source: EIA Gasoline and Diesel Fuel Update, published every Tuesday.
FAQ
How much does it cost to fuel a semi truck per mile?
At this week's national average of $4.578/gallon and 6.5 MPG, fuel costs about $0.70 per mile. Your number moves with diesel prices and your truck's real-world MPG.
How many gallons does a semi use per 100 miles?
A loaded Class 8 truck at 6.5 MPG burns about 15.4 gallons per 100 miles. Idling, terrain, and load weight push that up.
Where does the diesel price in this calculator come from?
The default is the U.S. On-Highway Diesel Fuel Price published by the EIA every Tuesday. You can type over it with your actual pump price.
Does this include DEF cost?
No. DEF typically adds 2-3% of fuel spend; add it on top if you want a fully loaded number.
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Fuel surcharge calculator · Cost per mile · This week's diesel prices
Data updated: 2026-07-06 · Source: EIA weekly diesel