Free Driving Distance Cost calculator with clear step-by-step results.
Fuel is only part of what a journey costs. Distance and consumption give the litres burned and therefore the fuel bill, but tyres, servicing intervals and depreciation all accrue per kilometre driven, and tolls and parking are real cash. Including a per-kilometre wear figure is what makes the total comparable against a train fare or a rental, which already have those costs built in.
Fuel
Fuel cost = distance ÷ 100 × consumption × price per litre
Total
Total = fuel cost + distance × wear per km + tolls and parking
Fuel prices, tolls and running costs vary by region and vehicle. Use your own recorded consumption and local prices for a figure you can rely on.
Around $0.05-0.12 per km covers tyres, servicing, brakes and fluids on a typical car. Official mileage reimbursement rates are higher because they also include insurance and depreciation.
For a like-for-like comparison against public transport, yes — add it to the wear figure. For deciding whether to make one extra trip in a car you already own, fuel plus wear is the marginal cost that matters.
Divide the total by the number of people sharing. Car travel gets cheaper per person with each passenger, which is often what makes it beat rail for a group.