Fuel Cost Calculator
The fuel cost of a trip from distance, MPG, and gas price.
Input sheet
DIY at your own risk. Calcora's calculators and guides are general estimates and information only — not professional, engineering, legal, or safety advice. Always verify local building codes and permit requirements, and hire a licensed pro for electrical, gas, plumbing, structural, or any work you're not fully comfortable doing yourself.
Before a road trip or commute decision, it helps to know the fuel bill up front. This calculator turns distance, your vehicle's MPG, and the pump price into a dollar figure for the drive.
How it works
Distance divided by MPG gives gallons used; times the price per gallon gives cost.
The logic is two simple steps: distance divided by MPG gives the gallons you will burn, and gallons times the price per gallon gives the cost. A round-trip figure doubles the one-way cost.
Real-world mileage runs below the EPA sticker in stop-and-go traffic, cold weather, or with a loaded vehicle, so use your observed MPG (miles driven ÷ gallons filled) rather than the brochure number for the most accurate estimate.
Trip cost = (distance ÷ MPG) × price per gallon.
Worked examples
300 miles at 28 MPG with gas at $3.45/gal. → $36.96 one way (about 10.7 gallons), or $73.93 round trip.
300 ÷ 28 = 10.71 gal; 10.71 × 3.45 = 36.96.
An 800-mile road trip at 32 MPG, gas at $3.45/gal. → $86.25 one way (25.0 gallons).
800 ÷ 32 = 25 gal; 25 × 3.45 = 86.25.
Tips & gotchas
- Use your real measured MPG, not the window-sticker number — highway driving usually beats it, city driving usually misses it.
- Highway speed matters: fuel economy drops sharply above about 60 mph, so a faster trip can cost noticeably more.
- For a fair comparison against flying or a rental, add the round-trip cost plus any tolls and parking.
- Carrying a roof box or heavy load cuts MPG by 10–25%; account for it on a packed vacation drive.
FAQ
Does this include tolls, parking, or wear?
No — it is fuel only. For a true cost-per-trip, add tolls, parking, and an allowance for maintenance and depreciation (often $0.10–$0.20 per mile).
How do I find my real MPG?
Fill the tank, reset the trip meter, drive normally, then refill and divide the miles driven by the gallons added. Average a few tanks for a reliable number.
How does this work for a hybrid or EV?
For a hybrid, use its observed MPG. For an EV the model does not apply directly — instead compute miles ÷ miles-per-kWh × electricity rate.
Related calculators
Unit Price Calculator · Dog Age Calculator · Age Calculator · Date Difference Calculator · Discount Calculator