Investment Calculator
Project an investment balance from an initial amount, monthly deposits, annual return, years and compounding frequency, with total deposits and interest earned.
Results · USD
Future value
Interest earned
- Total deposits
- $29,000.00
Growth over time· 10 years
Swipe chart horizontally if needed →
Year-by-year· 10 rows
- Year
- 1
- Balance
- $7,839.97
- Deposits
- $7,400.00
- Interest
- $439.97
- Year
- 2
- Balance
- $10,885.24
- Deposits
- $9,800.00
- Interest
- $1,085.24
- Year
- 3
- Balance
- $14,150.65
- Deposits
- $12,200.00
- Interest
- $1,950.65
Showing 3 of 10 rows — swipe the schedule below for the full table.
| Year | Balance | Deposits | Interest |
|---|---|---|---|
| 1 | $7,839.97 | $7,400.00 | $439.97 |
| 2 | $10,885.24 | $9,800.00 | $1,085.24 |
| 3 | $14,150.65 | $12,200.00 | $1,950.65 |
| 4 | $17,652.12 | $14,600.00 | $3,052.12 |
| 5 | $21,406.71 | $17,000.00 | $4,406.71 |
| 6 | $25,432.72 | $19,400.00 | $6,032.72 |
| 7 | $29,749.77 | $21,800.00 | $7,949.77 |
| 8 | $34,378.90 | $24,200.00 | $10,178.90 |
| 9 | $39,342.67 | $26,600.00 | $12,742.67 |
| 10 | $44,665.27 | $29,000.00 | $15,665.27 |
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Educational estimates · not financial advice · free, no signup
How this was calculated
Each period: balance ← balance × (1 + r/n) + deposit. Deposits assumed end-of-period. Default n = 12 (monthly).
Want more detail? Full formula notes & FAQs ↓
Detailed guide
What it is, how to use it, how to read the numbers, common mistakes, a worked example, formulas, and FAQs.
What this calculator is
Most people build wealth by investing a lump sum and then adding to it regularly. This calculator combines both: an initial balance, a monthly deposit, an assumed annual return, a term in years and a compounding frequency produce a projected balance, the total you deposited and the growth from returns. The result is a projection at a constant assumed return. Real investments fluctuate, may lose value, and carry fees and taxes that this tool does not model. Use it to compare scenarios, such as saving a little more or starting earlier, rather than as a forecast.
When to use / who it helps
- You are planning how a lump sum plus monthly saving could grow.
- You want to compare two return assumptions.
- You want to see how much of the final balance is your own money.
- You are testing the effect of starting earlier or later.
- You are choosing between saving more and chasing a higher return.
How to use
Steps
- Enter the starting balance.
- Enter the monthly deposit.
- Enter an assumed annual return; be conservative.
- Enter the number of years and choose the compounding frequency.
- Read the future value, total deposits and interest earned.
- Review the year-by-year table and chart for the path of growth.
How to interpret results
- Future value is the projected balance at the end of the term.
- Total deposits equal the initial amount plus all monthly deposits.
- Interest earned is the growth attributable to the assumed return.
- Small changes in return compound into large differences over decades.
- The projection excludes fees, taxes and inflation.
Common mistakes & gotchas
- Using an optimistic return as if it were certain.
- Ignoring fund fees and taxes.
- Forgetting inflation, so the future number buys less than it appears.
- Entering the annual deposit as a monthly deposit.
- Expecting a steady return when real markets move up and down.
Worked example
Worked example — $5,000 start, $200 a month, 7%, 10 years, monthly compounding
- Monthly rate: 0.07 ÷ 12 = 0.005833.
- Starting amount grows to 5,000 × (1.005833)^120 ≈ $10,048.
- Deposits grow like an annuity: 200 × ((1.005833)^120 − 1) ÷ 0.005833 ≈ $34,617.
- Total future value ≈ $44,665; total deposits are 5,000 + 200 × 120 = $29,000.
Result: About $44,665 after ten years, with roughly $15,665 coming from returns.
To load the form's own demo values, tap Try example above the Calculate button.
How to calculate / formula
Each period: balance ← balance × (1 + r/n) + deposit. Deposits assumed end-of-period. Default n = 12 (monthly).
Frequently asked questions
How much will my investment grow?
It depends on the return, which is uncertain. This tool shows the arithmetic for the rate you enter.
What return should I assume?
Use a conservative, diversified figure and test lower values too. No return is guaranteed.
Does compounding frequency matter?
Slightly. More frequent compounding increases growth a little at the same nominal rate.
Are deposits made at the start or end of the period?
At the end of each period in this calculator.
Does this include taxes and fees?
No. These reduce real returns.
How do I account for inflation?
Subtract expected inflation from the return to estimate a real return, or use the inflation adjuster.