Finance & investing · NUMORA
Simple Interest Calculator
You already have some, and you can add more each month. When is it enough?
Open interactive calculatorHow to use
I = P × r × t, total = P + I.
Formula
I = Prt
FAQ
Is this Simple Interest calculator accurate?
The formula and assumptions are shown on the page, and the engine is covered by audit tests. Results are for reference — not financial or medical advice.
Do I need an account?
No. Calculations run in your browser. Recents can stay on this device.
What inputs do I need?
I = P × r × t, total = P + I.
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