Compound Interest Calculator

Calculators

What is Compound Interest Calculator?

Compound Interest Calculator is a powerful financial planning utility that models the growth of investments over time. Described by Albert Einstein as the eighth wonder of the world, compound interest multiplies your money by earning interest on top of previously accumulated interest. This tool calculates the future value of your savings or investment portfolio, showing how initial deposits, monthly contributions, compounding frequencies, and interest rates interact over decades.

How it works

The calculator applies standard compound interest formulas: A = P * (1 + r/n)^(n*t) along with annuity math for recurring monthly deposits. It computes yearly balances, total contributions, and earned interest in real-time as you drag the sliders or change the values. All calculations are executed privately on your device.

Features & Benefits

Shows the exact power of compounding with a year-by-year breakdown
Supports annual, semi-annual, quarterly, monthly, and daily compounding
Runs entirely in your browser — no server, no data sent
Useful for savings accounts, bonds, CDs, and investment projections

Frequently Asked Questions

What is compound interest?

Compound interest means you earn interest on your interest, not just on the principal. Over time this snowballs — a key reason long-term investing is powerful.

How does compounding frequency affect growth?

More frequent compounding (monthly vs. annually) produces slightly more growth. The difference becomes meaningful over longer time horizons.

Does this account for regular contributions?

No — this calculator handles a single lump-sum principal. For regular contributions, the SIP / DCA approach requires a separate calculation.

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