Check whether a fuel detour pays off

Compare the pump-price saving with fuel used over the extra return distance, then consider time, tolls and wear separately.

Two stations
Find a station price
The same grade at the station further away.
Detour and fill
Counted there and back.
Vehicle

Each option shows the saving after the detour.

Fills in the fuel use. Or choose a size or enter your own figure below.
Vehicle

Example: 10 c/L cheaper, 5 km away

Example

Fuel-only saving after the detour

$3.21

Break-even at 14.0 km each way

Nearest price, U91 national average
223.8 c/L
Cheaper price
213.8 c/L
Price gap
10.0 c/L
Litres to fill
50 L
Saving on 50 L
$5.00
Fuel for the 10.0 km return (0.80 L at the nearest price)
$1.79
Fuel-only difference
$3.21
Time, tolls and vehicle wear are not included.

Example: 10 c/L cheaper, 5 km away. Fuel-only saving after the detour. $3.21. Break-even at 14.0 km each way

Saving after the detour · Break-even at 14.0 km each way$3.21

Details

Count the whole detour before chasing a lower price

  1. Use the same fuel grade

    Compare U91 with U91, diesel with diesel, and premium with the premium grade your vehicle requires.

  2. Enter the one-way detour

    Enter the extra distance to reach the station. The calculator doubles it to include the return trip.

  3. Use the litres you will buy

    A large cents-per-litre gap only creates a large saving when the fill itself is large enough.

  4. Value time and access

    Queue time, traffic, tolls, membership rules and opening hours can outweigh a small calculated saving.

Fuel map

Check a station price before you go

Open the fuel map for reported prices, update times and directions near you or along your route.

Get the free FuelRadar app

Free on iPhone and Android: price alerts, saved stations, the forecast.

Download on the App StoreGet it on Google Play

Detour calculator questions

How does this compare the detour?

Fuel saving = (nearest price − cheaper price) × litres ÷ 100. Detour fuel cost = one-way detour × 2 × fuel use, priced at the nearest station. Fuel-only difference = saving − detour cost. Time, tolls and vehicle wear are separate.

What is the break-even distance?

The longest one-way detour where the saving exactly covers the extra fuel. Drive any further than that and the detour costs more than it saves.

Is there a quick rule of thumb?

A larger fill and a bigger price gap support a longer detour; a thirstier vehicle shortens it. Use the break-even distance, then compare current reports on the fuel map.