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THE FEUTEX TOOLKIT

Rental Car Fuel Return Shortfall

Estimate fuel to buy to restore a rental tank to its starting fraction.

Travel workspace● Runs in your browser
01 Your input
02 Your result
View or copy raw result data
FormulaLitres = Math.max(0,start-current)*tank; Cost = Math.max(0,start-current)*tank*price

Made for real tasks

  • Estimate fuel to buy to restore a rental tank to its starting fraction.
  • Compare two scenarios by changing the inputs and rerunning the tool.
Explore step-by-step workflows →

Worked example

Inputs

Tank
50 L
Start
0.75 tank fraction
Current
0.3 tank fraction
Price
1.8 currency/L

Expected results

Litres
22.5 L
Cost
40.5 currency

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

  1. Enter tank, start, current, price.
  2. Use consistent units shown beside each input. Run the calculation and review the assumptions below.

Try this example

{
  "tank": 50,
  "start": 0.75,
  "current": 0.3,
  "price": 1.8
}

Accuracy and scope

Fuel gauge assumed linear; actual tank shape and rental return policies vary.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.