Compound Interest Calculator
Starting amount, rate and years in; final value out, with the growth shown year by year. Optional monthly deposits.
Example — $1,000 at 5% for 10 years$1,628.89
How we got it — the example, step by step
- Growth formula: A = P × (1 + r/n)^(n×t) = 1,000 × 1.05^10.
- 1.05^10 ≈ 1.628895, so A = 1,000 × 1.628895 = $1,628.89.
- Of that, $1,000 is the money put in — the interest earned is $628.89.
Check it backwards
The year-by-year table multiplies by the same 1.05 growth factor each year and lands on $1,628.89 in year 10.
Questions people also ask
What does the compounding frequency change?
How often interest is added — yearly, quarterly, monthly. More frequent compounding grows slightly faster, because interest starts earning interest sooner.