Fuel Cost Calculator for One-Way or Round Trips with Per-Person Split

This tool is a straightforward way to predict trip expenses without hunting for external data. Start with the distance you plan to drive and choose whether you want a one-way result or a round trip. The “Round trip” selector doubles the distance automatically so you don’t have to do the mental math. Next, enter your vehicle’s fuel economy and the fuel price you pay locally. The math is transparent and immediately shows total fuel needed, total cost, and a per-person split for easy cost-sharing.

Units and currency are detected from your browser to remove friction. In most countries, the calculator defaults to kilometers and liters; in the United States it switches to miles and mpg automatically. Labels and the small chips inside each field update live: the distance box shows km or mi, and the price box shows per L or per gal so you always know exactly what the number represents. If your car displays efficiency in a specific format, just pick those units here and type the reading directly—no conversion required.

Here’s how to think about your inputs. The distance should reflect the actual road length you expect to travel, not the straight-line distance. For consumption, enter either L/100 km (lower is better) or mpg (higher is better) depending on your unit choice. Entering the real price you pay removes the need for any live price feeds and keeps the result accurate for your context. The calculator computes fuel needed first, then multiplies by your price to get the total. If you add passengers, the per-person line shows a fair split immediately.

• Metric example: 240 km at 6.5 L/100 km, price 1.95 per L → fuel ≈ 15.6 L → cost = 15.6 × 1.95.
• US example: 180 mi at 30 mpg, price 3.90 per gal → fuel ≈ 6.0 gal → cost = 6.0 × 3.90.
• Round trip: switch on and the distance doubles before calculations, so fuel and cost scale accordingly.
• Per-person: total cost divided by the number of people in the car.

The headline numbers are designed for fast decisions: the total cost is formatted in your currency and the per-person figure sits next to it for quick splits. A compact key-value summary lists distance, consumption, local price, fuel needed, and totals so you can sanity-check every assumption. Because the calculator is input-driven, there’s nothing to maintain and no chance of stale information. You can also copy a prefilled link with the Share button to coordinate planning with friends or coworkers.

To keep things simple and portable, the tool doesn’t model hills, weather, or traffic. If you want a conservative estimate, nudge consumption upward a little or round the price to today’s higher station. For fleet or recurring routes, save a permalink with your typical efficiency, price, and passenger count; then just adjust distance week to week. The same approach works when you’re renting a car abroad—switch the units, type the posted fuel price, and you’ll get a clean estimate that matches the local market.

Finally, for clarity and discoverability: this is a Fuel Cost Calculator for One-Way or Round Trips with Per-Person Split. That exact phrase describes what the tool computes and matches the heading at the top of the page, so people who search for a fast, transparent fuel estimate can recognize it instantly. If you keep your inputs realistic, the output will be equally practical.

Metric path: liters = (distance_km × L/100 km) ÷ 100; total cost = liters × price per L. US path: gallons = distance_mi ÷ mpg; total cost = gallons × price per gal. If round trip is selected, distance is doubled before applying either formula. Per-person = total cost ÷ people. That’s the whole model—clear, reproducible, and easy to verify.