Finance & trading

How much will savings grow with compound interest?

Final amount with starting capital, monthly contributions, annual rate and years.

Quick answer

Future value with monthly compounding: FV = P × (1 + r/12)^(12×t) + PMT × [((1 + r/12)^(12×t) − 1) ÷ (r/12)]. €5,000 start, €200/month, 6% annual for 20 years → roughly €109,000 total (€53,000 contributed, €56,000 interest).

Final amount

08,959.20

Total contributed
$53,000.00
Interest earned
$55,959.20

Simulation at a constant rate with monthly compounding. Real returns vary over time.

How it works

Compound interest means you earn returns on prior returns — the curve accelerates over time. Real investments fluctuate; this calculator assumes a constant rate. Fees, taxes and inflation reduce the real outcome.

Frequently asked questions

Compound interest vs simple interest?+

Simple interest applies only to the principal. Compound applies to principal plus accumulated interest — growth is exponential. At 6% over 20 years, compounding roughly doubles the interest earned vs simple on the same principal.

What annual return is realistic?+

Global stock markets averaged roughly 7–10% nominal long-term before inflation; balanced portfolios 4–6%. Savings accounts and bonds are lower. Past performance does not guarantee future returns — use conservative assumptions for planning.

Does contribution timing matter?+

Monthly vs annual contributions differ slightly because earlier deposits compound longer. Investing at month-start vs month-end shifts the result marginally. Consistency beats timing — start early.

How does inflation affect the result?+

Subtract inflation from the nominal rate for real purchasing power. 6% return with 2% inflation ≈ 4% real growth. €109,000 in 20 years buys less than today’s €109,000 — plan in real terms for retirement goals.

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