Fuel Cost Calculator — Trip & Commute Cost
Home › Everyday Calculators › Fuel Cost Calculator
Free Fuel Cost Calculator — Trip Gas Cost, Cost per Mile & Monthly Commute
Estimate how much your trip will cost in fuel. Works in MPG, L/100km, or km/L. Choose one-way or round trip, see cost per mile, and calculate your monthly commute spend. Formula shown every time.
⛽ Calculate Your Trip Fuel Cost
How to Use This Fuel Cost Calculator
Mode 1 — Trip Cost
- Select your efficiency unit — MPG for US drivers, L/100km for most of Europe and Asia, km/L for South Asia.
- Choose one-way or round trip — round trip automatically doubles the distance.
- Enter distance, fuel efficiency, and fuel price — results appear instantly.
- Add passengers (optional) — to split the fuel cost per person for carpools or road trips.
Mode 2 — Monthly Commute
Enter your one-way commute distance, car efficiency, fuel price, and working days per month to see your daily, monthly, and yearly fuel spend on commuting.
Fuel Cost Formulas — All Unit Systems
🇺🇸 MPG (US)
Gallons = Distance ÷ MPG
Cost = Gallons × Price/gal
Example: 300 miles ÷ 30 MPG = 10 gal × $3.50 = $35
🌍 L/100km
Liters = Distance × (L/100km ÷ 100)
Cost = Liters × Price/liter
Example: 400 km × (8 ÷ 100) = 32 L × $1.20 = $38.40
🏍️ km/L
Liters = Distance ÷ km/L
Cost = Liters × Price/liter
Example: 300 km ÷ 15 km/L = 20 L × $1.10 = $22
Fuel Efficiency Conversion Table
| MPG (US) | L/100km | km/L | Vehicle Type |
|---|---|---|---|
| 15 MPG | 15.7 L/100km | 6.4 km/L | Large SUV / Truck |
| 20 MPG | 11.8 L/100km | 8.5 km/L | Average SUV |
| 25 MPG | 9.4 L/100km | 10.6 km/L | Average sedan |
| 30 MPG | 7.8 L/100km | 12.7 km/L | Fuel-efficient sedan |
| 40 MPG | 5.9 L/100km | 17.0 km/L | Hybrid vehicle |
| 50+ MPG | 4.7 L/100km | 21.3 km/L | Plug-in hybrid / EV range extender |
Real-World Examples
Distance: 500 miles (round trip)
Car: 28 MPG | Gas: $3.60/gal
Fuel = 500 ÷ 28 = 17.86 gal
Total = $64.29
One-way: 12 miles (24 round)
Car: 25 MPG | Gas: $3.50/gal
Monthly (22 days) = $74.18
Annual = $890
Trip: 200 miles | 22 MPG
Gas: $3.80/gal | 4 passengers
Total = $34.55
Per person = $8.64
Distance: 400 km | 7 L/100km
Fuel: $1.50/liter
Liters = 400 × 0.07 = 28 L
Total = $42.00
💡 10 Proven Ways to Reduce Your Fuel Cost
- Maintain proper tire pressure — under-inflated tires reduce MPG by up to 3%.
- Drive at consistent speeds — highway speeds of 55–65 mph are typically most efficient.
- Avoid rapid acceleration and hard braking — smooth driving improves efficiency by 10–40%.
- Remove unnecessary weight — every 100 lbs of extra load reduces MPG by ~1%.
- Use cruise control on highways to maintain constant speed.
- Keep your engine maintained — dirty air filters and spark plugs reduce efficiency.
- Plan and combine trips — cold engines use more fuel; combining errands saves gas.
- Carpool when possible — sharing a ride splits the cost among passengers.
- Shop for gas prices — prices can vary 20–40¢ per gallon between nearby stations.
- Consider a more efficient car — upgrading from 20 MPG to 30 MPG saves ~$500/year at $3.50/gal and 15,000 miles/year.
Frequently Asked Questions
How do I calculate the fuel cost for a road trip?
Divide your trip distance by your car's MPG to get gallons needed, then multiply by the gas price. Formula: Cost = (Distance ÷ MPG) × Price per gallon. For a 300-mile trip at 30 MPG with gas at $3.50: (300 ÷ 30) × $3.50 = 10 × $3.50 = $35. Use the calculator above for instant results.
How do I convert MPG to L/100km?
Divide 235.21 by the MPG figure. Example: 30 MPG = 235.21 ÷ 30 = 7.84 L/100km. To convert the other way: L/100km to MPG = 235.21 ÷ L/100km. A lower L/100km number means more efficiency; a higher MPG number means more efficiency.
How much do I spend on fuel per year for commuting?
Use the Monthly Commute tab above. Enter your one-way distance, car MPG, and gas price. The calculator shows your daily, monthly, and annual commute fuel cost automatically. The average American spends approximately $1,500–$3,000 per year on commute fuel depending on distance, car efficiency, and local gas prices.
What MPG should I use — city or highway?
Use highway MPG for motorway/freeway trips and city MPG for urban driving. For mixed trips, use the combined MPG figure from your car's specifications. Important: real-world MPG is typically 10–15% lower than EPA-rated MPG due to driving habits, traffic, AC use, and road conditions. Use actual MPG from your fill-up records for the most accurate estimate.
How do I find my car's actual fuel efficiency?
Fill your tank completely. Drive normally. When the tank is near empty, fill up again and note the miles driven and gallons added. Divide miles driven by gallons added to get your real-world MPG. Do this over 3–4 fill-ups and average the results for the most accurate figure. This is always more accurate than the EPA sticker rating for your actual driving conditions.
Comments
Post a Comment