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Gas Trip Cost Calculator

Fuel cost for a trip, split among passengers if you're carpooling.

🔒 Runs entirely in your browser — nothing here is ever uploaded

About the Gas Trip Cost Calculator

Estimates the fuel cost for a trip from distance, your vehicle's fuel economy, and the current gas price — with an option to split the cost among passengers.

100% Free Runs in Your Browser No Sign-Up Required
How to use it
  1. Enter the one-way trip distance and whether it's round trip.
  2. Enter your vehicle's combined fuel economy (mpg) and the current gas price.
  3. Enter the number of people splitting the cost, if any.
  4. Read the total fuel cost and cost per person.
Formula
Effective distance = one-way distance × 2 if round trip, else one-way distance. Gallons needed = effective distance ÷ mpg. Total fuel cost = gallons needed × price per gallon. Cost per person = total fuel cost ÷ number of people.
Worked example

A 300-mile round trip (600 miles total) at 32 mpg and $4.08/gallon, split among 3 people: about $76.50 total fuel cost, or $25.50 per person.

Interpreting your result

This is a straight-line fuel-cost estimate — (distance ÷ mpg) × price per gallon — it doesn't model traffic, elevation, HVAC load, or driving-style effects on real-world mileage. Use your vehicle's combined mpg (window-sticker rating or your dashboard's actual trip average) rather than splitting city/highway separately. Splitting among passengers divides the total fuel bill evenly and doesn't account for who's actually driving. This doesn't include tolls, parking, or wear-and-tear — pair it with the Car Total Cost of Ownership Calculator for a fuller per-mile estimate.

Recommendations
  • Real-world mpg often runs somewhat below the window-sticker combined rating, especially with highway speeds, AC/heat use, or a loaded vehicle — use your dashboard's actual trip average if you have it for a more accurate estimate.
  • Gas prices vary significantly by state and even by station along a route — check prices at your actual likely fill-up points rather than relying on a single national average for a long trip.
  • This doesn't account for tolls, parking, or wear-and-tear — pair it with the Car Total Cost of Ownership Calculator for the fuller picture of what a trip really costs.
Frequently asked questions
No — this calculates fuel cost only. Add tolls, parking, and any other trip-specific costs separately.