Simple Interest Calculator
Calculate simple (non-compounding) interest from a principal, annual rate and number of years, and see the interest earned plus the total. Handy for short-term loans and quick estimates. Runs in your browser.
- 100% free
- Private & safe
- Runs in your browser
Why use Simple Interest Calculator?
Simple Interest Calculator gives you accurate results instantly, with the underlying formula shown so you can trust the numbers.
- Runs instantly in your browser — nothing to install, nothing uploaded.
- Completely free, with no account, no watermarks and no usage limits.
- Interest = Principal × Rate × Time
- Enter the principal.
- Works on any device — desktop, tablet and phone — and is fully keyboard accessible.
How to use Simple Interest Calculator
- Enter the principal.
- Enter the annual rate and years.
- See interest and total.
- Adjust to compare.
Examples
- $1,000 at 5% for 3 years earns $150.
- Estimating interest on a short personal loan.
Formulas
- Interest = Principal × Rate × Time
Limitations
- Simple interest doesn't compound; use the compound tool for that.
- Estimate only, not financial advice.
Frequently asked questions
What's the difference from compound interest?
Simple interest is charged only on the principal; compound interest also charges interest on accrued interest.
Is my data stored?
No — it's calculated in your browser.
Can rate be monthly?
Enter an annual rate; convert monthly rates to annual first.
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Compound Interest CalculatorSee how savings grow with compound interest and contributions.Loan CalculatorEstimate monthly payments, total interest and a full amortization schedule.Investment CalculatorEstimate investment growth from contributions and returns.Savings CalculatorProject savings growth from regular deposits and interest.