Monthly Investment Growth Calculator
Investment Calculator
Investment Parameters
End Balance
$0.00
Total Contributions
$0.00
Total Interest
$0.00
Investment Breakdown
Investment Growth Over Time
Investment Schedule
| Year | Deposit | Interest | Ending Balance |
|---|
The investment calculator projects how much a lump sum or regular monthly investment grows over time at a specified annual return rate. It uses compound growth to show the full power of long-term investing.
How Investment Growth Is Calculated
FV = P(1 + r)^n + C x [(1 + r)^n - 1] / r
FV = future value. P = initial investment. r = annual return rate (as decimal). n = years. C = annual contribution. Example: $10,000 starting, $200/month, 8% return, 20 years = $133,650.
Growth by Return Rate and Time
| $10,000 invested with $200/month | 5% Return | 8% Return | 10% Return |
|---|---|---|---|
| 10 years | $46,774 | $52,656 | $57,017 |
| 20 years | $95,985 | $133,650 | $162,798 |
| 30 years | $171,872 | $297,281 | $410,914 |
| 40 years | $289,836 | $624,614 | $1,007,892 |
Dollar-Cost Averaging
Dollar-cost averaging means investing a fixed amount at regular intervals (monthly, weekly) regardless of market price. When prices fall, you buy more shares. When prices rise, you buy fewer. Over time, this produces a lower average cost per share than a single lump-sum investment made at market peak. It also removes the stress of timing the market.
Investment Return Benchmarks
| Asset Class | Historical Annual Return (approximate) | Risk Level |
|---|---|---|
| US Savings Account | 0.5-5% | Very low |
| US Treasury Bonds (10yr) | 3-5% | Low |
| Balanced Portfolio (60/40) | 6-7% | Moderate |
| US Large Cap Stocks (S&P 500) | 10% (7% after inflation) | High |
| Small Cap Stocks | 11-13% | Higher |
Frequently Asked Questions
How much will $10,000 grow in 10 years?⌄
At 7% annual return, $10,000 grows to approximately $19,672 in 10 years with no additional contributions. With $100/month added, it grows to $36,800. Return rate and additional contributions are the biggest drivers. This calculator shows exact projections for any inputs.
What is a realistic investment return to expect?⌄
Broad stock market index funds (like S&P 500) have returned roughly 10% annually before inflation and 7% after inflation over long periods. A diversified portfolio of stocks and bonds typically projects 6-8% depending on the allocation. No return is guaranteed.
How much should I invest per month?⌄
A common guideline is to invest 15% of gross income for retirement. If you earn $60,000/year, aim for $750/month. Start with what you can afford and increase by 1-2% each year. The amount matters less than starting early and staying consistent.
Is it better to invest a lump sum or monthly contributions?⌄
Research consistently shows lump-sum investing outperforms dollar-cost averaging about two-thirds of the time, since markets tend to rise over time. However, most people do not have a large lump sum available. Monthly contributions are the practical reality and still produce excellent long-term outcomes through dollar-cost averaging.
What is compound growth in investing?⌄
Compound growth means your gains generate their own gains. If your $10,000 earns 10% ($1,000) in year one, you now have $11,000 earning the next year's return. Over decades, this exponential growth produces dramatically more wealth than simple growth. This is why time in the market matters more than timing the market.