Automotive Costs: Loans, Fuel Economy & EV Charging Guide
Understanding vehicle ownership costs, miles per gallon, depreciation, and charging.
📚 Overview
Vehicles are often the second-largest purchase households make. Calculating true cost of ownership—including financing interest, depreciation curves, fuel efficiency, and electric vehicle charging rates—helps drivers make financially sound automotive choices.
📐 Miles Per Gallon (MPG) & EV Charging Duration
Fuel cost per mile = Gas Price / MPG. EV cost per mile = (Electricity Rate $/kWh × Consumption kWh/100mi) / 100.
🔢 Worked Example
Scenario: A driver travels 360 miles on a 12-gallon tank of fuel priced at $3.60 per gallon.
- Distance: 360 miles
- Fuel: 12 gallons
- Price: $3.60/gallon
- MPG = 360 / 12 = 30 MPG
- Cost per mile = $3.60 / 30 = $0.12 per mile
- Annual fuel cost (15,000 miles) = 15,000 × $0.12 = $1,800
💡 Pro Tips
- Depreciation is the largest hidden vehicle expense, accounting for roughly 40% of a new car's value over its first three years.
- Properly inflated tires improve fuel economy by up to 3% while extending tread lifespan.
- Level 2 EV home charging (240V / 32–48A) provides 25 to 35 miles of range per hour of charge time.
- Use our auto loan calculator to understand the true impact of dealer interest rate markups.
🧮 Automotive Calculators (13)
Put the formulas above into practice with these free tools:
Fuel consumption in L/100 km, km/L, and miles per gallon.
Monthly car payment, interest, and total cost.
Estimated car value after several years.
Cost to charge an electric car between two battery levels.
Overall diameter, sidewall height, and circumference from a tire code.
Monthly lease payment from price, residual value, term, and rate.
Engine size in cc, liters, and cubic inches from bore and stroke.
Total ownership cost of a vehicle per distance unit driven.
❓ Frequently Asked Questions
Is electric vehicle charging cheaper than gasoline?
In most regions, charging an EV costs roughly 1/3 to 1/2 the equivalent cost of gasoline per mile driven.
What does the 20/4/10 rule for buying cars mean?
Put at least 20% down, finance for no longer than 4 years, and keep total monthly vehicle costs under 10% of gross income.
How is vehicle depreciation calculated?
Typically, new vehicles lose 20% of their value in year one, and approximately 10% to 15% each year thereafter.