Road trip gas cost calculator
Planning a road trip? Enter where you're starting and where you're going — the calculator finds the driving route, takes its real road miles and works out the gallons of gas and the money the trip will take.
- Gas needed
- 10 gal
- Gas cost
- $35
- Drive time
- 4 h 15 min
Routes are looked up through Apple Maps (MapKit JS) only when you press the button. Brimly doesn't store your places or routes.
How it's calculated
The route comes from Apple Maps road data: the calculator finds both places, asks for the driving route and takes its distance and time. Then gallons = miles ÷ mpg, and cost = gallons × gas price. Adjust any number by hand — the result updates instantly.
Getting a number you can trust
- Use your own average mpg, not the window sticker — in real driving most cars land 10–20% below the EPA combined rating.
- A road-trip number is closer to your highway mpg: a steady 65 mph uses noticeably less gas than stop-and-go city traffic.
- Add about 10% for detours, traffic and mountain grades — the router measures the road, not your driving day.
Ask the AI assistant about your trip
Planning the drive? Ask the free assistant what to check on the car before a long trip, how to cut gas use on the highway, or what to expect from your model — 10 free questions a day, no sign-up.
The assistant is answering…
That's 10 for today
The free web limit resets tomorrow. In the Brimly app the assistant knows your specific car — its real mileage, fuel log, and service history.
Requires iOS 18.1 or later. Free to download, with optional in-app purchases.
The conversation is stored only in your browser — we don't keep it on our servers.
AI answers can be inaccurate and don't replace a professional diagnosis.
Brimly does this automatically: it knows your car's real mpg from your fill-ups, prices a trip in one tap — and checks maintenance before you leave.
Requires iOS 18.1 or later. Free to download, with optional in-app purchases.