Home / Compound Interest Calculator

Compound Interest Calculator

See how your investment grows over time, with optional monthly contributions.

Quick Presets

Future Value

-
-

Initial Investment

-

Total Contributions

-

Total Interest Earned

Effective Annual Return: -

🔵 Contributed   🟢 Interest Earned

Growth Over Time

Annual Growth Schedule

Compare Two Scenarios

Plan A

Plan B

Free Compound Interest Calculator — See Your Investment Grow

Compound interest is often called the eighth wonder of the world for good reason — it lets your money earn returns not just on your original investment, but on all the interest it has already accumulated. Our free Compound Interest Calculator projects your investment's future value, including optional monthly contributions, using the standard compound growth formula.

Why Use This Tool

  • Monthly contribution support: Model regular deposits, not just a one-time investment.
  • Flexible compounding: Choose annual, quarterly, monthly, or daily compounding.
  • Full breakdown: See total contributed vs. interest earned separately.
  • Multi-currency support: Works with your local currency label.

Key Features

Visual Growth Bar

See contributed vs. interest earned.

Compounding Frequency

Annual, quarterly, monthly, or daily.

Step-by-Step: How to Use

Step 1: Enter your principal amount and select currency.

Step 2: Optionally enter a monthly contribution amount.

Step 3: Enter your expected annual interest rate and time period.

Step 4: Select a compounding frequency and click "Calculate" to see your future value.

Benefits

  • Helps visualize the long-term power of consistent saving and investing.
  • Useful for comparing different interest rates or contribution amounts.
  • Provides a clear separation between contributed capital and earned interest.

Common Use Cases

  • Projecting retirement savings growth over several decades.
  • Comparing bank savings account interest rates before choosing one.
  • Planning a child's education fund with regular monthly contributions.
  • Understanding how compounding frequency affects investment returns.

Privacy & Security

A = P(1 + r/n)^(nt), plus future value of monthly contributions compounded at the same rate. Where P is principal, r is annual rate, n is compounding frequency per year, and t is time in years. All calculations happen locally in your browser.

Frequently Asked Questions

How is monthly contribution handled? +
Each contribution is treated as a new deposit earning compound interest for its remaining time in the investment.
More frequent compounding (daily) yields slightly higher returns than annual at the same rate.
A = P(1 + r/n)^(nt).
Simple interest is on principal only; compound interest is on principal plus accumulated interest.
Enter your principal, rate, and 10 years to see the projection.
No, this shows nominal growth only.
Yes, completely free with unlimited calculations.
No, all calculations happen locally in your browser.
Yes, commonly used to project long-term retirement growth.
Interest earning interest leads to significantly larger growth over time.

Related Tools

Also try our Salary Calculator and Loan & EMI Calculator.

Ready to see your investment grow? Enter your details above — free and instant.

Share Your Experience

Found this tool useful? Have a suggestion or found a bug? Send your feedback directly to us — we read every message.