Finance

Simple interest

Calculate simple interest (I = principal × rate × time) and the total.

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Calculate simple interest

Enter the principal, the annual rate and the time: get the interest and the total. The bar shows the share of principal and interest.

  1. Principal

    The starting amount.

  2. Rate and time

    % per year and years.

  3. Read the result

    Interest + total.

Where it applies

  • Some simple-interest loans
  • Fixed-coupon bonds
  • Compare a simple offer to compound
  • Quick estimates

Example: 1,000 at 5%, 3 years

ItemValue
Principal1,000
Rate × time5% × 3 years
Interest150
Total1,150

Formula: principal × rate × time. Indicative estimate, 100% local calculation, not financial advice.

Frequently asked questions

What is the formula?

Interest = principal × (annual rate ÷ 100) × time in years. The total is the principal plus the interest. Simple interest is computed only on the starting principal.

Difference from compound interest?

Simple interest always applies to the initial principal. Compound interest is added to the principal and earns interest itself, giving a higher total over time.

Is my data private?

Yes. Everything is computed in your browser; nothing is sent or stored.

Is this financial advice?

No. It is an indicative calculation. Real terms (fees, taxes, compounding) may differ.