This investment calculator projects portfolio growth from an initial deposit, regular contributions, and an expected annual return.
Finance
Investment Calculator
Model investment growth with initial amount, contributions, return and years.
Calculator
About this calculator
Formula notes
Each period: balance = balance × (1 + r/12) + contribution, compounded monthly over the term.
Worked examples
- Example: 10000 initial plus 2000/month at 8% for 10 years grows to about 722864, of which 290000 is your own contributions.
- Starting with $10,000, adding $300 monthly, and assuming 7% annual growth produces a projected balance near $62,000 after 10 years, before fees, taxes, and inflation.
How to use it
- Enter the starting amount and monthly contribution.
- Enter the expected annual return and years.
- Read the ending balance split into contributions vs growth.
Frequently asked questions
Is the 8% return guaranteed?
No. It is an assumption — long-run stock index averages have historically been around 7–10% nominal.
Why does growth accelerate over time?
Compounding earns returns on past returns, so the curve bends upward in later years.
Limits and interpretation
- A constant annual return smooths out volatility and cannot show loss sequences or the probability of reaching the projection.
- Nominal ending value does not express purchasing power unless inflation, tax, and fees are considered separately.