Simple Interest Calculator

Modify the values and click the Calculate button to use

End Balance: $26,000.00

Principal: $20,000.00
Interest Rate: 3%
Term: 10 years (120 months)
Total Interest: $6,000.00
End Balance: $26,000.00

Principal vs interest

Principal$20,000.0076.9%
Total interest$6,000.0023.1%

Schedule

Year	Interest	Balance
1	$600.00	$20,600.00
2	$600.00	$21,200.00
3	$600.00	$21,800.00
4	$600.00	$22,400.00
5	$600.00	$23,000.00
6	$600.00	$23,600.00
7	$600.00	$24,200.00
8	$600.00	$24,800.00
9	$600.00	$25,400.00
10	$600.00	$26,000.00

Balance growth over the term

Balance

What this simple interest calculator does

Simple interest is calculated only on the original principal. It does not compound, so the interest earned each period stays the same.

This calculator estimates total interest and the ending balance from a principal, annual interest rate, and term in years and months.

How to use this calculator

Enter the principal.
Enter the annual interest rate.
Enter the term in years and months.
Click Calculate to see the total interest and ending balance.

Simple interest formula

I = P × r × t
A = P + I

P is the principal, r is the annual interest rate as a decimal, and t is the term in years. I is the total simple interest and A is the ending balance.

What the results include

Principal: the original amount.
Total interest: simple interest over the term.
End balance: principal plus total interest.
Term: the number of months used.

Frequently asked questions

What is the difference between simple and compound interest?

Simple interest is calculated only on the principal. Compound interest is calculated on the principal plus previously earned interest.

Does this calculator support monthly rates or monthly terms?

The core version uses an annual rate and a term in years and months. Monthly rate bases and other rate conventions are not included.

Can I calculate the principal from an ending balance?

This version calculates the ending balance from the principal. The reverse calculation is not included.

Source

Reference: Investor.gov — Compound Interest Calculator.

Disclaimer

This calculator is for informational and planning purposes only. It is not financial advice. Confirm the rate and term with the lender or financial institution.

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