About this calculator

How-to: enter your starting balance, monthly contribution, expected annual return and time horizon. We compound monthly: FV = P(1+r/12)^n + PMT × ((1+r/12)^n − 1)/(r/12). Try a realistic 6–7% real return for a diversified stock portfolio; 3–4% for bonds. Interest earned is the difference between the future value and total contributions.

Frequently asked questions

What return should I assume?

Long-run US equities have returned ~10% nominal / 7% real. A diversified 60/40 portfolio historically returns 5–7% real. Use 6% as a conservative planning assumption.

Monthly vs annual compounding — big difference?

Small. Monthly vs annual compounding at 7% is a difference of ~0.2% per year — inputs matter far more than frequency.

Should I include inflation?

For real purchasing power, subtract expected inflation (2–3%) from your return. So a 7% nominal return is ~4–5% real.

What does the Compound Interest & Wealth Projection Calculator do?

Project long-term wealth from a starting balance, recurring contributions and an annual return, with year-by-year compounding. How-to: enter your starting balance, monthly contribution, expected annual return and time horizon. We compound monthly: FV = P(1+r/12)^n + PMT × ((1+r/12)^n − 1)/(r/12). Try a realistic 6–7% real return for a diversified stock portfolio; 3–4% for bonds. Interest earned is the difference between the future value and total contributions.

Is the Compound Interest & Wealth Projection Calculator free to use?

Yes. Every calculator on Calcurly.com is free, works in your browser without sign-up, and can be embedded on your own website.

How accurate is the Compound Interest & Wealth Projection Calculator?

Results are calculated in real time using industry-standard formulas. Treat the output as a well-informed estimate — always cross-check with local regulations, product datasheets, or a qualified finance professional before committing to a purchase or a job.

What inputs does the Compound Interest & Wealth Projection Calculator need?

Enter values for: Starting balance, Monthly contribution, Annual return (%), Time horizon (years), Currency. Sensible defaults are pre-filled where possible so you can start with a single change.

Can I embed the Compound Interest & Wealth Projection Calculator on my own website?

Yes — copy the iframe snippet at the bottom of this page, or use the Embed Generator to customise the size. The embedded version stays in sync with the live calculator on Calcurly.com.