Compound Interest Calculator
Model monthly compounding with a starting balance and end-of-month contributions.
Example result
- Total contributions including start
- 34,000
- Hypothetical interest
- 16,969.84
Fixed nominal rate, monthly compounding and contributions at month-end. Tax, fees and inflation are excluded. The rate is hypothetical.
How to calculate it
Fixed nominal rate, monthly compounding and contributions at month-end. Tax, fees and inflation are excluded. The rate is hypothetical.
Worked example
This is an illustrative scenario, not a market benchmark. Select “Reset to example” to reproduce it in the calculator.
- Starting balance
- 10,000 currency units
- Monthly contribution
- 200 currency units
- Nominal annual interest rate
- 6 %
- Time horizon
- 10 years
Projected balance: 50,969.84
Compound Interest FAQ
What happens at a 0% rate?
The final balance equals starting capital plus all contributions. The calculation uses that exact zero-interest case.
What does this calculation leave out?
Fixed nominal rate, monthly compounding and contributions at month-end. Tax, fees and inflation are excluded. The rate is hypothetical.
Are my inputs saved or sent to a server?
Calculations run in your browser. We do not send your inputs or results to our server or analytics. A comparison stays in this tab until it is refreshed. A CSV is saved only when you choose to download it. See our privacy policy for ordinary hosting and optional analytics data.
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