Compound Interest with Contributions
Project account growth with a starting balance, recurring contributions, annual return rate, and time horizon.
| 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.
How it works
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
When to use this tool
This tool is designed for quick, practical tasks such as everyday calculations, data formatting, or simple conversions. It is best used when you need fast results without installing software or using complex tools.
When to use
- Quick checks or one-time calculations
- Validating or converting data before using it elsewhere
- Simple tasks that do not require advanced software
When not to use
- Critical financial, legal, or medical decisions
- Large-scale or automated processing
- Situations requiring guaranteed precision beyond basic validation
Always review results before using them in important contexts.
About this tool
This tool helps you perform quick utility operations directly in your browser. It runs entirely in your browser without sending data to a server.
You can use this tool when handling simple tasks without installing additional software. The results should be interpreted as a processed output based on your input data.
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.