Trip Fuel Cost Estimation Guide
A fuel cost calculator estimates the total trip cost from your distance, fuel economy (mpg or L/100 km), and fuel price. It also shows fuel required and cost per mile (or km) so you can compare routes and vehicles.
What is Fuel Cost Calculator?
The fuel cost calculator converts trip plans into dollars by combining your vehicle's efficiency with local fuel price. It supports multiple segments, unit conversion (mpg, L/100 km), and cost-per-mile analysis.
How to Use the Fuel Cost Calculator
- Enter distance for your trip (mi or km).
- Provide fuel economy as mpg or L/100 km (toggle units).
- Enter fuel price per gallon or per liter.
- (Optional) add segments with different prices or speeds.
- Calculate total fuel needed, trip cost, and cost per mile/km.
Formulas & Methods
- Gallons needed:
Gallons = Distance_mi / MPG - Liters needed:
Liters = Distance_km * (L_per_100km) / 100 - Total cost:
Cost = Fuel_needed * Price_per_unit - Cost per mile:
CPM = Cost / Distance_mi - mpg <-> L/100 km:
L/100km = 235.215 / mpg(US gal);mpg = 235.215 / L/100km
Assumptions & limitations
- Real economy varies with speed, grade, wind, AC, tires, and load.
- Prices differ by station and time; use your expected price on trip day.
- For EVs, use the EV Range or energy cost method (kWh and $/kWh).
Examples
Example A — US units
Distance 420 mi, economy 28 mpg, price $3.80/gal
Gallons = 420/28 = 15, Cost = 15 * 3.80 = $57.00, CPM = $0.136.
Example B — Metric
Distance 700 km, economy 6.8 L/100 km, price 1.65 per liter
Liters = 700 * 6.8 / 100 = 47.6, Cost = 47.6 * 1.65 ~ 78.54, Cost/km ~ 0.112.
| Input | Value | |---|---| | Distance | 420 mi | | Economy | 28 mpg | | Price | $3.80/gal | | Fuel needed | 15 gal | | Total cost | $57.00 |
Pro Tips & Best Practices
- Use recent average mpg from your car's trip computer for realistic results.
- Lower speed slightly on long highways to improve mpg and reduce costs.
- Check tire pressure and remove roof racks to reduce drag.
- Compare alternate routes if they differ in speed/grade.
Related Calculators
FAQ
Q: How do I estimate trip fuel cost?
A: Enter trip distance, fuel economy (mpg or L/100 km), and fuel price. The calculator multiplies gallons/liters needed by price.
Q: What is the difference between mpg and L/100 km?
A: mpg is distance per volume (higher is better). L/100 km is volume per distance (lower is better).
Q: How accurate is the estimate?
A: Traffic, speed, AC usage, terrain, and payload affect real economy. Use your car's recent average for best accuracy.
Q: Can I include multiple legs or stops?
A: Yes, add segments with different distances, speeds, or prices and the tool totals the cost.
Q: Does cruise speed affect fuel use?
A: Yes—higher speeds increase aero drag; economy often drops above 60-70 mph (100-115 km/h).
Call to Action
Enter distance, economy, and price to see fuel needed, total cost, and cost per mile—then optimize your route or speed to save.