Sharing a car for a road trip is one of the cheapest ways to travel — as long as everyone chips in fairly for gas. This splitter turns the distance, your car's MPG, and the pump price into a per-person amount in seconds.
How the split works
Divide the trip distance by your MPG to get the gallons needed, multiply by the price per gallon for the total, then divide evenly by the number of people. For a round trip, enter the full there-and-back distance.
Some groups also split tolls and parking the same way, or have passengers cover gas while the driver covers wear and tear — whatever feels fair for your trip.
A worked example
A 500-mile road trip in a 30-MPG car uses about 16.7 gallons; at $3.50 a gallon that's roughly $58, so four people split to about $14.58 each. Add a fifth passenger and each share drops to about $11.67 — the more people in the car, the cheaper it gets per head, which is a big part of why carpooling saves money.
Splitting it fairly
Even splits are the simplest approach, but groups handle it in different ways. Some have passengers cover fuel while the driver absorbs wear and tear and the cost of providing the car; others split tolls and parking the same way as gas. If people join or leave partway, you can prorate each share by the miles they actually rode.
The real trick is agreeing up front — settle the method before you set off, and nobody's stuck doing awkward math at a gas station at the end of the trip.