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THE FEUTEX TOOLKIT

Invoice Late Fee Scenario

Calculate simple late-payment interest and a fixed fee using an entered contract rate and day count.

Business workspace● Runs in your browser
01 Your input
02 Your result

How to use this tool

  1. Enter your values in the labelled fields or load the worked example.
  2. Review the assumptions below, then run the tool.
  3. Review the result, then copy or download it.

Try this example

{"principal": 1000, "annualRate": 8, "days": 30, "yearBasis": 365, "fixedFee": 0}

Accuracy and scope

Does not decide legal enforceability. Use the agreed rate, allowed fees and correct day-count basis.

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.