Fuel Cost Calculator
Gas cost for any trip — and what your commute really costs per week, month, and year
Related calculators
All automotive- MPG CalculatorReal gas mileage from a fill-up, with MPG ↔ L/100km conversions
- Road Trip Cost CalculatorBudget gas, hotels, food, and activities with a per-person split
- Commute Cost CalculatorDaily, monthly, and annual cost of driving to work with wear
- EV Savings CalculatorCompare electric vs gas fuel cost per year, per mile, and lifetime
- Auto Insurance EstimatorRough car insurance premium estimate from your driver profile
- Car Lease CalculatorLease payment from cap cost, residual, and money factor — real dealer math
Quick summary
Fuel cost = distance ÷ MPG × gas price. A 300-mile trip in a 30-MPG car at $3.50/gallon uses 10 gallons and costs $35 — about 12¢ per mile. Switch on commute mode (days per week) to see the weekly, monthly, and annual bill: a 20-mile each-way commute at those numbers runs about $1,213 a year in gas alone.
Reviewed by Simple Calculators TeamLast reviewed
How to use this calculator
- Enter the inputs requested by the calculator.
- Choose the units or options that match your situation and review the assumptions.
- Run or update the calculation to see the result.
- Review the result, breakdown, and formulas shown on the page.
- Check the inputs, units, dates, and limitations before saving or sharing the result.
Frequently asked questions
How do I calculate fuel cost for a trip?
Divide the distance by your car's MPG to get gallons, then multiply by the price per gallon: 300 miles ÷ 30 MPG × $3.50 = $35. Use your real-world MPG (often 10–15% below the EPA sticker) for accurate numbers.
How much does commuting cost in gas?
A typical 20-mile each-way commute in a 28-MPG car at $3.50/gallon costs about $5 per day — roughly $25/week, $108/month, and $1,300/year. Fuel is usually only 30–40% of total driving cost once depreciation, insurance, and maintenance are counted.
What's the cost per mile of driving?
For gas alone: price per gallon ÷ MPG. At $3.50 and 30 MPG that's 11.7¢/mile. The IRS all-in standard mileage rate (70¢/mile in 2025) is a good proxy for the true total cost including wear and depreciation.
How can I cut my fuel cost?
The biggest levers: drive smoothly (aggressive acceleration costs 15–30% at highway speeds), keep tires inflated (~3%), remove roof racks (~5–25% at speed), and comparison-shop gas apps — a 30¢/gallon spread is common within a few miles.
Key terms
- MPG
- Miles per gallon — your car's fuel economy. Real-world MPG is usually below the window-sticker rating.
- Cost per Mile
- Gas price ÷ MPG — the marginal fuel cost of each mile driven.
- Round Trip
- Double the one-way distance — the toggle handles it so commute math uses the full daily drive.
Methodology, sources & limitations
This page shows the formula, assumptions, and limitations used for this estimate. Rates, thresholds, and other time-sensitive inputs can change, so verify them against the relevant official source before relying on a result.
For our review approach and the primary sources we consult, see the methodology and source policy. If you spot an outdated figure or formula, please contact us with a correction.