Calculate the late fee or interest owed on an overdue invoice. Choose simple or compound interest, set your rate and payment date, and see the penalty amount instantly — free and without signup.
Multiply the outstanding invoice amount by the daily interest rate, then multiply by the number of days overdue.
Compound interest applies interest to both the original amount and any previously accrued interest, increasing the penalty over time.
No. All calculations happen in your browser.
Yes, completely free with no signup.