Trip Gas Cost Calculator
Add each leg of a trip, include any tolls, and see the total gas cost -- split evenly between however many people are riding along.
EIA weekly average, week of September 14, 2026 -- a starting point, not your local price.
Splits fuel + tolls evenly.
Total trip distance
315 mi
507 km
Fuel cost
$39.36
Total cost (fuel + tolls)
$51.86
Per person (3)
$17.29
How it's calculated
Every leg's distance is summed in kilometers, then converted to a fuel cost the same way the main Fuel Cost Calculator does, with tolls added afterward:
total distance = leg 1 + leg 2 + ... (converted to a common unit)
total cost = (fuel needed × price per liter) + tolls
per-person cost = total cost ÷ passengers
Worked example
The calculator's own defaults: two legs (150 mi and 165 mi), 28 mpg (US), gas at $3.50/gal, $12.50 in tolls, split 3 ways.
| Total distance | 315 mi |
| Fuel cost | $39.36 |
| Total cost (fuel + tolls) | $51.86 |
| Per person | $17.29 |
Frequently Asked Questions
How is the estimated gas cost for a trip worked out?
Every leg's distance is converted to kilometers and summed, then run through the same fuel-needed and cost formula as the main Fuel Cost Calculator. Tolls are added on top before the total is split between passengers -- this gives you what the trip actually costs to make, not just the fuel.
Why enter legs separately instead of one total distance?
Splitting a trip into legs (home to the first stop, first stop to the next, and so on) matches how most real road trips are planned -- from a map app's leg-by-leg mileage -- and makes it easy to add or remove a stop without re-adding the whole route's distance by hand.
Can I mix miles and kilometers between legs?
Yes -- each leg has its own mi/km toggle, useful for a trip that crosses into a country using the other system. Every leg is converted to a common unit before the total is calculated.
What if I don't know my exact fuel economy?
Use the MPG Calculator on a recent fill-up to get a real number instead of a guess or a manufacturer rating, then bring that figure back here.
Does the per-person cost split tolls too?
Yes -- the per-person figure splits the combined fuel cost and tolls evenly across the number of passengers you enter, not just the fuel.
These are estimates; real consumption varies with driving, load and conditions. This site isn't affiliated with any vehicle manufacturer, utility, or the US Energy Information Administration -- see the Terms.