About this simple interest calculator
Estimate non-compounding interest over a chosen period. Interest equals principal multiplied by the annual percentage rate and the number of years. Final amount is principal plus that interest. Use this workspace to prepare a result you can review before putting it to use. All processing takes place on your device, without an account or an upload of your inputs. Check the examples to understand the expected output, read the limitations for the supported scope, and reset the form when you want to start a separate task.
How it works
Interest equals principal multiplied by the annual percentage rate and the number of years. Final amount is principal plus that interest.
Try these examples
Principal 1000; rate 5%; 2 years
Interest 100; final amount 1100
Principal 500; rate 4%; 0.5 years
Interest 10; final amount 510
Limitations & privacy
Illustrative arithmetic only. Principal up to 1 trillion, rate 0–100%, term 0–100 years. Excludes compounding, fees, taxes, day-count conventions and changes in rate.
Inputs and results stay in this browser. Only tool identifiers are stored for your recently used tools. You can clear that history from the directory.
A few good questions
How is the result produced?
Interest equals principal multiplied by the annual percentage rate and the number of years. Final amount is principal plus that interest.
Are my inputs sent to a server?
No. Inputs and results are processed locally and are not uploaded or included in telemetry. Copying or downloading is your choice.
What are the limits of this tool?
Illustrative arithmetic only. Principal up to 1 trillion, rate 0–100%, term 0–100 years. Excludes compounding, fees, taxes, day-count conventions and changes in rate.
Updated September 19, 2026