Finance
Compound Interest Calculator
Chart investment growth over time by blending an initial deposit, recurring contributions, and flexible compounding schedules.
Plot investment growth with periodic contributions and customizable compounding cadence.
Growth Projection
Future value with contributions
FV = P(1 + r/n)ⁿᵗ + C × [((1 + r/n)ⁿᵗ − 1) ÷ (r/n)]
P is the starting balance, C is the contribution per period, r is the annual rate, n is the number of compounds per year, and t is the number of years invested.
How to use
- Enter your starting balance and the contribution you plan to add each period.
- Provide the annual return rate, years invested, and compounding frequency.
- Scan the projection to compare total contributions versus growth generated by compounding.
Example
Input: Initial deposit = $10,000, Contribution = $200 monthly, Rate = 7%, Years = 15, Compounding = Monthly
Output: Future value ≈ $91,881.93 (Growth ≈ $45,881.93 over $46,000 contributed)
FAQ & notes
How do I model weekly or daily compounding?
Use the compounding selector to match the institution’s schedule. The formula automatically adjusts n to daily (365) or weekly (52) when chosen.
Can I skip contributions entirely?
Yes. Set the contribution to zero and the calculator reverts to the classic compound interest formula using only the initial deposit.