Guide · True cost

Fuel is the tip. Here's the iceberg.

Everyone feels fuel — it's the expense with a pump and a receipt. But the honest cost of a car is fuel + service + insurance + tyres + everything else. Add it all up and two magic numbers appear: cost per km, and cost per month. They change how you drive, maintain, and buy.

6 min read · by the FuelCap team

The categories nobody adds up

Individually they're all forgettable. Together they're the car's real price:

None of these show up in one place — except in a tracker where every fill, service and expense lands in the same ledger. That ledger produces the two numbers worth knowing.

Cost per km, cost per month

Total spend over a period ÷ distance driven = cost per km. Total spend ÷ months = cost per month. That's it — no spreadsheet needed if the tracker does the division continuously. And for the version that includes the purchase price itself, try the true cost calculator.

What they reveal:

Using your data for the next purchase

This is where tracking quietly pays for itself. When it's time to change cars, your own history answers questions no review can:

Spec sheets are the same for everyone. Your logs are yours — that's the edge.

Common questions

How do I calculate the total cost of running my car?

Add fuel, service, insurance, tyres, registration, parking and everything else over a period; divide by distance for cost per km, by months for cost per month. A tracker computes both continuously as you log.

How much of running cost is fuel?

Usually the biggest single recurring line, but insurance and servicing rival it for low-usage drivers. Only your own logs give the honest split — that's rather the point.

Should my fuel data influence my next car purchase?

Yes — real cost per km and usage patterns beat brochure figures. Your logs know whether you're a city-short-trip driver or a highway commuter, and that changes which powertrain actually wins the math.

Know the number nobody adds up.

Total spend, cost per km, cost per month — from your own fills, services and expenses. Free.