Fuel Stop Planner
Plan fuel stops for a road trip.
Enter trip distance and tank range to find how many fuel stops you need and optimal spacing.
How Gas Station Cost Calculations Work
Finding the cheapest gas near your route can save meaningful money on long trips. The calculation involves fuel efficiency, distance, price per gallon, and whether a detour to a cheaper station is actually worth the extra miles.
Basic fuel cost formula:
Fuel Cost = (Distance ÷ MPG) × Price per Gallon
Worked example:
- Trip distance: 350 miles
- Vehicle fuel economy: 28 MPG
- Gas price: $3.45/gallon
Gallons needed = 350 ÷ 28 = 12.5 gallons Trip cost = 12.5 × $3.45 = $43.13
Detour worthiness formula:
Savings = (Cheaper price − Regular price) × Tank size Detour cost = (Extra miles ÷ MPG) × Gas price Worth it if: Savings > Detour cost
Example — is a 3-mile detour worth it?
- Regular price: $3.60/gallon
- Cheaper station: $3.40/gallon
- Tank capacity: 15 gallons
- Savings: ($3.60 − $3.40) × 15 = $3.00
- Detour cost: (6 miles ÷ 28 MPG) × $3.50 = $0.75
- Yes, it’s worth the detour — net savings of $2.25
Price per mile formula:
Cost per mile = Gas price ÷ MPG
At $3.50/gallon and 30 MPG, every mile costs $0.117.
Tips for finding the best price:
- GasBuddy and Google Maps show real-time prices reported by drivers
- Prices are typically lowest Tuesday–Wednesday mornings
- Wholesale club stations (Costco, Sam’s Club) are often $0.10–$0.25 cheaper per gallon
- Highway exit stations typically charge 10–20% more than nearby town stations