How is simple interest different from compound interest?

Simple interest is calculated only on the principal, while compound interest is also calculated on accumulated interest.

Simple Interest Calculator

Simple interest accrues only on the original principal, unlike compound interest. Use this to calculate interest for short-term loans or investments.

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Formula

I = P × r × t

Simple Interest vs. Compound Interest: The Formula Difference That Matters

Why simple interest grows in a straight line while compound interest curves upward, with a side-by-side example.

Compound Interest Calculator

See how your savings or investments grow with compound interest over time.

Loan Calculator

Calculate monthly payments for any personal, auto, or business loan.

Mortgage Calculator

Estimate your monthly mortgage payment, total interest, and payoff schedule.

ROI Calculator

Calculate return on investment as a percentage and annualized rate.

CAGR Calculator

Calculate the Compound Annual Growth Rate of an investment.

Savings Goal Calculator

Find out how much to save each month to reach a financial goal.