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Fuel Cost Calculator for Trips

Fuel needed and trip cost in any unit, split between passengers.

Use via API

Fuel needed and cost of a trip from distance, fuel efficiency (L/100 km, km/L, US or UK MPG) and fuel price, optionally round trip and split between people. Send JSON, get JSON back.

POST https://pithlab.com/api/v1/tools/fuel-cost-calculator

curl https://pithlab.com/api/v1/tools/fuel-cost-calculator \
  -H "Authorization: Bearer $PITHLAB_KEY" \
  -H "Content-Type: application/json" \
  -d '{"distance":350,"distanceUnit":"km","efficiency":6.5,"efficiencyUnit":"l-100km","price":1.75,"priceUnit":"litre","roundTrip":true,"people":2}'

Fields and responseOpenAPI documentGet an API key

About the Fuel Cost Calculator

Work out how much fuel a journey needs and what it costs, using MPG (US or UK), L/100 km or km/L, with round trips and splitting the cost between passengers.

How to use the Fuel Cost Calculator

  1. Enter the distance in kilometres or miles and tick round trip if you're coming back the same way.
  2. Enter your car's fuel efficiency in the unit you know (L/100 km, km/L, US MPG or UK MPG) and the fuel price per litre or gallon.
  3. Read the fuel needed and the total cost, and enter the number of people to split it fairly between passengers.

Examples

Round trip of 150 km each way, two people

Input

150 km, round trip, 6.5 L/100 km, 1.80 per litre, 2 people

Output

Round trip of 300 km at 6.5 L/100 km uses 19.5 L of fuel, costing 35.10 (17.55 each for 2 people).
US road trip

Input

250 miles, 30 MPG (US), 3.50 per US gallon

Output

Trip of 250 mi at 30 mpg (US) uses 8.33 US gal of fuel, costing 29.17.
UK car, priced per litre

Input

200 miles, 45 MPG (UK), 1.45 per litre

Output

Trip of 200 mi at 45 mpg (UK) uses 20.2 L of fuel, costing 29.30.

Frequently asked questions

Why are US and UK MPG different?

A UK (imperial) gallon is 4.546 litres and a US gallon is 3.785 litres, so the same car does about 20% more miles per gallon in UK figures. 30 MPG (US) is roughly 36 MPG (UK) and 7.8 L/100 km.

How do I convert MPG to L/100 km?

Divide 235.21 by US MPG, or 282.48 by UK MPG. For example, 30 MPG (US) is 235.21 ÷ 30 ≈ 7.84 L/100 km. You don't need to convert here: just pick the unit you have.

How accurate is the estimate?

It is as good as the efficiency figure you enter. Real consumption rises with speed, traffic, hills, air conditioning and roof boxes, so official figures are often optimistic. Your own recent average is the best number to use.