Simple Interest Calculator
Calculate noncompounding interest and the final balance from a principal, annual rate and explicit time basis.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Convert the entered duration to years. Divide the annual percentage rate by one hundred. Multiply principal by rate and time without compounding. Add interest to principal and compare intermediate balances.
I=P r t; final balance=P+I
Worked example
A principal of 1000 at 5% simple annual interest for 2 years earns 100 interest and ends at 1100.
Assumptions and input details
One fixed simple rate; interest never earns interest. Day-based results use the entered days per year. Fees, taxes, compounding and dated day-count conventions are excluded.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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