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Built for gearheads

Fuel

Fuel Cost Calculator

Estimate the total fuel cost for any trip using distance, expected MPG, and current gas price. Built for road-trippers, fleet owners, and side-hustle drivers.

What this calculator is for

A fuel cost calculator estimates trip spend from distance, MPG, and price per gallon — the simple math gas stations and fleet managers use: gallons needed × local fuel price.

Plan road trips, compare driving vs flying for regional travel, or see how much a roof rack and 75 mph cruising cost over 500 miles. Use realistic MPG from your logs, not only the EPA sticker.

Pair with the MPG calculator if you need to convert a recent fill-up into MPG first.

Calculator

How to use this calculator

  1. Enter trip distance in miles, your expected MPG, and local price per gallon.
  2. Use realistic MPG (not EPA sticker) for road trips.

Use highway MPG you actually log for long trips — EPA highway is often optimistic at 80 mph with a loaded vehicle.

Mountain grades and headwinds can add 20–40% fuel use versus flat cruise — pad the estimate for western hauls.

Update fuel price for the states you cross — prices vary significantly.

Towing halves effective MPG on many gas trucks — model trailer loads separately.

The math: do it without a calculator

Gallons = Distance ÷ MPG

Trip cost = Gallons × Price per gallon

Example: 500 mi ÷ 22 MPG ≈ 22.73 gal × $3.50/gal ≈ $79.55.

Gallons = Distance ÷ MPG. Trip cost = Gallons × Price per gallon.

Example: 500 mi ÷ 22 MPG ≈ 22.73 gal × $3.75/gal ≈ $85.24.

Cost per mile = trip cost ÷ distance — useful to compare two vehicles on the same route.

Real-world examples

Road trip fuel budget

820 miles at 22 MPG needs about 37.3 gallons. At $3.75 per gallon, fuel cost is about $140 — simple distance ÷ MPG × price, the same math gas stations use on a long highway haul.

Daily commuter cost

45 miles per day round trip, 28 MPG, five days a week, at $3.50/gal is roughly $28 per week in fuel (before insurance and maintenance). Useful for comparing a truck versus a compact car before changing jobs or routes.

Troubleshooting & fine-tuning your setup

Trip Fuel Cost Estimates vs What You Actually Pay

If the trip cost is lower than reality, your MPG input is probably optimistic or you forgot mountain grades, headwinds, and A/C load. Towing can cut MPG in half versus unloaded highway numbers.

Fuel price varies by state and station — update price per gallon for the region you will drive through on long hauls. EV and hybrid drivers should use energy cost tools instead; this calculator is gallons-based.

Frequently asked questions

Road Trip Fuel Cost FAQs

Should I use EPA highway MPG for road trips?

Use your logged highway MPG or subtract 10–15% from EPA if you have no history. Loaded vehicles and 75+ mph driving usually beat EPA highway.

How much does towing increase fuel cost?

Expect 30–50%+ higher consumption with a medium travel trailer versus solo — sometimes more in mountains. Model towing MPG separately.

Does ethanol blend change cost per mile?

E10 often costs less per gallon but MPG may drop slightly. Compare cost per mile: (price ÷ MPG), not price per gallon alone.

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