Compound Interest with Contributions
Project account growth with a starting balance, recurring contributions, annual return rate, and time horizon.
Compound Interest with Contributions tool
| Year | End value | Total contributions | Estimated gain |
|---|
Monthly mode uses monthly compounding by default. Yearly mode uses yearly compounding.
Informational only. Assumes a constant growth rate and does not include taxes, fees, or inflation.
In monthly mode, the annual return is divided into monthly periods and applied repeatedly over time. Contributions are added either at the beginning or end of each period, depending on your selection.
The result separates total contributions from estimated gain so you can see how much of the future value comes from new deposits versus projected growth.
Examples
- $5,000 start + $300/month at 7% for 20 years
- $10,000 start + $2,000/year at 5% for 15 years
- Switch contribution timing to “Beginning of period” to model earlier deposits
FAQ
- What does this calculator estimate?
It estimates the future value of an account using compound growth plus recurring contributions over time.
- What is the difference between principal and contributions?
Principal is the starting amount. Contributions are the extra amounts added regularly after the start.
- Can I choose contribution frequency?
Yes. You can choose monthly or yearly contributions.
- Does this include taxes, fees, or inflation?
No. This is a gross mathematical projection only. It does not include taxes, fees, or inflation adjustments.
- Are results guaranteed?
No. This calculator assumes a constant return rate for estimation purposes only.