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FREE INVOICE GENERATOR / GOOD TO KNOW

Late payment interest calculator

Estimate simple interest using a rate and overdue period you supply.

PLAN WITH CLARITY

Your numbers. A clear answer.

Calculated on your device. Values are not saved or sent to a server.

RESULTS
Estimated simple interest
$0.00
Principal plus interest
$0.00

Results are estimates based on your entries. Currency is a display choice, not an exchange-rate conversion. Rounding occurs for display.

How the calculation works

Simple interest = principal × annual rate ÷ 100 × days ÷ 365.

A worked example

A principal of 1,000 at 12% for 30 days accrues about 9.86 using a 365-day year.

Use the result carefully

This does not determine whether interest can lawfully be charged. Use only an applicable, agreed rate. The calculation excludes compounding, fixed fees and legal collection costs.

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