Fuel Cost Calculator
Reviewed by Zyncalc Expert Team · Last updated June 2026 · Formula verified against official sources
Calculate fuel needed and total trip cost — compare two vehicles side by side.
Vehicle 2 cost: $50.00 · Difference: $12.50
About the Fuel Cost Calculator
Fuel cost is the second-largest expense of vehicle ownership after depreciation. Even small differences in fuel efficiency translate to large savings over time. A 35 MPG car driving 12,000 miles per year at $3.50 per gallon costs about $1,200 annually; a 25 MPG car costs $1,680 — a $480/year difference, or nearly $5,000 over 10 years.
Use the comparison feature when shopping for a new vehicle to see the real fuel-cost gap. Combine the comparison with the price difference between vehicles to find your true total-cost-of-ownership winner. Hybrids and EVs often have higher upfront costs but pay back through lower running costs over time.
Manufacturer-stated MPG numbers are based on standardized tests that often overstate real-world efficiency. EPA estimates are usually within 10% of actual; aggressive driving, short trips, cold weather, and rooftop cargo all reduce real MPG. Your trip computer is the most reliable source for your actual figures.
For long road trips, plan ahead with apps like GasBuddy to find the cheapest stations along your route. Skipping premium fuel when your car doesn't need it saves 20–50 cents per gallon. Maintaining proper tire pressure can improve MPG by 3%.
Frequently Asked Questions
MPG vs L/100km?+
Higher MPG = better. Lower L/100km = better. They're inverse units of efficiency.
How accurate is manufacturer MPG?+
Usually within 10% of real-world. Hybrids tend to outperform EPA in city driving.
Should I buy premium fuel?+
Only if your owner's manual requires it. Otherwise it's a waste of money.
Do EVs really cost less to drive?+
Yes — typically 1/3 the per-mile cost of gas vehicles.
What hurts MPG most?+
Aggressive acceleration, high speeds (>65 mph), short trips, and rooftop cargo.
Disclaimer: The results provided by this calculator are for informational and educational purposes only. They do not constitute financial, medical, legal or professional advice. Always consult a qualified professional before making important decisions based on these calculations.