Investment Calculator
Project lump-sum growth, model regular contributions, or work out how much to invest to reach your goal. Universal — works in any currency.
Try a worked example
How to Use This Calculator
Tab "Growth Projection"
Enter your initial investment, an annual return rate, and the number of years you plan to stay invested. The calculator shows your projected future value, total return, and how many times your money has multiplied. Use the year-by-year breakdown to see the power of compounding over time.
Tab "Regular Contributions"
Add an initial investment (can be zero) and a regular contribution — monthly or annual. The calculator shows your projected future value split into two components: money you contributed versus money earned from returns. This split reveals how much of your final pot is "free money" from compound growth.
Tab "Reach a Target"
Enter your target amount, expected return rate, and time horizon. Choose whether to calculate the required monthly contribution or the lump sum you need today. If you already have some money invested, enter that as the existing initial investment to reduce the gap.
The Formulas
FV = PV × (1 + r)t
FV = future value PV = present value (initial investment)
r = annual return rate (decimal) t = years
With regular contributions:
FV = PV × (1 + r)t + PMT × [((1 + r)t − 1) / r]
PMT = annual contribution amount
Required monthly contribution:
PMTannual = (FV − PV × (1 + r)t) × r / ((1 + r)t − 1)
Monthly = PMTannual ÷ 12
Required lump sum (present value):
PV = FV ÷ (1 + r)t
All formulas use annual compounding. Monthly compounding — used by most savings accounts and investment platforms — will produce slightly higher results because interest compounds more frequently. The difference is typically 0.3–0.5% on the final value over long periods.
Worked Examples
Example 1: $10,000 at 8% for 25 years
You invest a one-time lump sum of $10,000 in a diversified index fund and leave it untouched for 25 years, targeting an 8% average annual return.
Your $10,000 grows to $68,485 — more than 6.8 times your original investment — purely from compound growth. The key insight: you earned $58,485 without investing another penny. That is the power of time in the market.
Example 2: $10,000 + $500/month at 7% for 30 years
You start with $10,000 and consistently add $500 per month for 30 years at a 7% average annual return.
You personally put in $190,000. Compound growth added another $416,438 on top — more than twice what you contributed. Over 68% of your final portfolio came from returns, not your own money. This is the multiplier effect of consistent investing.
Example 3: Reach $1,000,000 in 20 years at 8%
You want to accumulate $1,000,000 in 20 years. You have no existing savings and expect an 8% annual return.
You would need to invest $1,698 per month to hit $1,000,000 in 20 years. Alternatively, a single lump sum of $214,548 today would reach the same target with no further contributions. Starting earlier dramatically reduces the monthly amount needed — at 30 years, the same target only requires $671/month.
Choosing a Return Rate
| Asset class | Typical nominal return | Notes |
|---|---|---|
| Global equities (index funds) | 7–10% per year | Long-term average; volatile year to year |
| Balanced portfolio (60/40) | 5–7% per year | Mix of stocks and bonds |
| Government bonds | 2–4% per year | Lower risk, lower return |
| High-yield savings / cash | 1–5% per year | Varies with central bank rates |
| Real estate (rental yield + appreciation) | 4–8% per year | Highly location-dependent |
To project inflation-adjusted (real) returns, subtract expected inflation (typically 2–3%) from the nominal rate. A 7% nominal return with 3% inflation equals roughly 4% real return.
Frequently Asked Questions
Calculate for your country
This universal calculator uses pure financial maths with no tax data. For country-specific calculations that include local tax treatment of investments (capital gains, dividend tax, tax-advantaged accounts):