Personal Finance
Simple Interest Calculator
Simple interest I = P r t and total amount.
Free to use — no sign-up or login.
Interest
Total
Amortization schedule
| # | Date | Payment | Principal | Extra | Interest | Balance |
|---|---|---|---|---|---|---|
This free Simple Interest Calculator covers Simple interest I = P r t and total amount.
Simple interest grows linearly with time (no compounding). Related personal finance tools sit beside How it works, with no account required.
Using the Simple Interest Calculator
Simple interest I = P r t and total amount. Typical inputs are Principal ($), Annual rate (%) and Years. How it works beside the form states the identity the Simple Interest Calculator applies.
Worked example
Principal $1,000 at 5% per year for 3 years: I = 1000 × 0.05 × 3 = $150. Total A = 1000 + 150 = $1,150.
\[ I=1000\times 0.05\times 3=150 \]
FAQ
When should I use simple instead of compound interest?
Simple interest grows linearly (I = Prt). Compound interest adds interest to the balance. Short-term notes sometimes quote simple interest; savings accounts usually compound.
Sources
Assumptions and limitations
Personal finance figures are illustrative. Taxes, insurance, fees, and lender overlays are omitted unless a field names them. This is not financial advice.
Rate is treated as a decimal fraction of 1 per year (5 means 5%).