Time & DateUpdated Aug 2026

Fuel Cost Calculator

Estimate the gas cost for any trip from distance, fuel efficiency, current fuel price, and passengers. Works for any vehicle.

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Updated 2026

What is a fuel cost calculator?

A fuel cost calculator estimates how much a trip costs in gas based on distance, vehicle fuel efficiency, current fuel price, and the number of passengers splitting the cost. It works for any vehicle — car, SUV, truck, motorcycle — and accepts miles or kilometers, mpg or L/100km, and USD per gallon or per liter. The output is total fuel cost, gallons needed, cost per mile, and cost per passenger for splitting.

Fuel Cost Calculator

$

Trip fuel cost

Total cost:

$37.50

Gallons needed:

10.71 gal

Cost per mile:

$0.13/mi

Cost per passenger:

$37.50

Conversion: 1 mile = 1.609 km; 1 gallon = 3.785 L; mpg to L/100km = 235.215 ÷ mpg. Real-world MPG varies with driving conditions, traffic, weather, and cargo.

Trip cost at $3.50/gal

Distance@ 20 mpg@ 30 mpg@ 40 mpg
100 miles$17.50$11.67$8.75
250 miles$43.75$29.17$21.88
500 miles$87.50$58.33$43.75
1000 miles$175.00$116.67$87.50

Verified accuracy

Cross-checked against authoritative formulas (IRS, NIST, ACM) and updated for 2025/2026 tax years and rates.

Instant results

No server roundtrip. All math runs in your browser so results appear the moment you finish typing.

Your data stays private

We never collect, store, or transmit your inputs. Every calculation runs locally in your browser.

Learn as you calculate

Each calculator includes the formula, plain-English explanation, and FAQs so you understand the result.

Estimates only. Calculator results are for educational and planning purposes — not professional advice. For binding decisions on taxes, investments, health, or legal matters, consult a qualified professional.

FAQ

Frequently asked questions

Everything you need to know about this calculator. Can't find what you're looking for? Email our team.

A fuel cost calculator is a free trip-planning tool that estimates how much gas a road trip will cost. Our fuel cost calculator needs four inputs: trip distance, vehicle fuel efficiency (mpg or L/100km), current fuel price (per gallon or per liter), and number of passengers (to split the cost). The fuel cost calculator returns total cost, gallons needed, cost per mile, and cost per passenger — useful for planning road trips, comparing driving to flying, or reimbursing mileage.

How it works

How to estimate the gas cost for a trip

Our fuel cost calculator computes the cost of a road trip from distance, fuel efficiency, current fuel price, and the number of passengers.

  1. 1

    Enter trip distance and unit

    Type the one-way or round-trip distance in miles or kilometers. The fuel cost calculator handles the conversion automatically.

  2. 2

    Enter fuel efficiency

    Type your vehicle's fuel economy in mpg (US) or L/100km (Canada/Europe). The fuel cost calculator converts between the two. Use your actual MPG if you know it from your own fill-up tracking; otherwise use the EPA combined rating from the window sticker.

  3. 3

    Enter fuel price and passengers

    Type the local fuel price per gallon or per liter. Add the number of passengers to split the cost evenly if applicable. The fuel cost calculator recomputes everything as you type.

  4. 4

    Read the result

    The fuel cost calculator shows total trip cost, gallons of fuel needed, cost per mile, and cost per passenger if splitting. A reference table below shows typical costs at common distances and MPGs.

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