Compounding Interest Calculator: see what time can do
At age 35, $50,000 invested plus $500 a month could grow to about $761,524 by age 65 at a smooth 6% annual return. Use the timeline to project investing for retirement or another long-term goal. The result is illustrative, before tax, fees and inflation.
- Free, no email
- Saves on your device
- Canadian dollars
What this calculator answers
Enter four numbers you likely know: your current age, target age, amount already invested and monthly contribution. The calculator shows the future balance, separates your money from estimated growth, and compares starting now with waiting five years.
Your timeline
The target age sets how long the current balance and future contributions have to grow.
Choose a target age at or after the current age.
Your investing path
One fixed assumption keeps this first pass simple: a smooth 6% return each year, before investment fees, tax and inflation. Real returns do not arrive smoothly and can be negative.
A worked 30-year example
The calculator opens at age 35 with $50,000 invested, $500 added each month, and age 65 as the target. That target could represent retirement or another long-term investing milestone.
| Age | Years of growth | Projected balance |
|---|---|---|
| 35 | Starting point | $50,000 |
| 40 | 5 years | $100,734 |
| 45 | 10 years | $168,627 |
| 50 | 15 years | $259,484 |
| 55 | 20 years | $381,070 |
| 60 | 25 years | $543,781 |
| 65 | 30 years | $761,524 |
Waiting five years to begin the $500 monthly contributions, while leaving the starting $50,000 invested, produces about $616,362 at 65. The difference is $145,162 in this smooth example.
How the compounding projection works
The current balance gets the full timeline
The money already invested compounds for every year between the current age and target age. The projection assumes the return stays at 6% each year. Actual investments move unevenly, including years with losses.
Monthly contributions are annualized
The tool multiplies the monthly contribution by 12 and treats that amount as arriving at the end of each year. Investing throughout the year can produce a slightly different result.
The answer is in future dollars
Inflation is not subtracted. A balance of $761,524 in 30 years will have less buying power than $761,524 has today if prices rise. The Financial Consumer Agency of Canada explains that inflation reduces the buying power of savings over time.
Using this projection for retirement
The target age can be your planned retirement age. This result projects only the investments entered here; it leaves out CPP or QPP, OAS, employer pensions, part-time income and future withdrawals. The Government of Canada's Canadian Retirement Income Calculator brings those sources together for a fuller estimate.
Government sources, checked 23 August 2026: the Financial Consumer Agency of Canada's Planning and saving for retirement guide and the Government of Canada's Canadian Retirement Income Calculator.
Questions people ask
How much could my investments grow to?
The answer depends on the starting balance, monthly contributions, time and returns. The worked example grows $50,000 plus $500 a month to about $761,524 over 30 years at a smooth 6% annual return before tax, fees and inflation.
How is the future balance calculated?
The current balance compounds annually at 6%. Monthly contributions are multiplied by 12, treated as a yearly amount, and added at the end of each year.
Is a 6% return guaranteed?
No. Six percent is an illustrative assumption. Actual returns depend on what is held, how markets perform, the timing of gains and losses, fees and tax. Some years may be negative. Test the result as a teaching example rather than a promise.
Are the results in today's dollars?
No. These are future dollars because inflation is not subtracted from the 6% return. The number at your target age may buy less than the same amount buys today. The FIRE calculator uses a real-return input when you want to work in today's dollars.
Can I use this to project investing for retirement?
Yes. Set the target age to your planned retirement age. The result covers only the investments entered here, so use the Canadian Retirement Income Calculator for a fuller estimate that includes CPP or QPP, OAS, employer pensions and other retirement income.
Does this calculator save or send my information?
Your figures are stored in this browser so the calculator remembers them next visit. Nothing is transmitted, no account is created, and no email address is asked for. Clearing browser data clears the saved figures.
Where to go next
FIRE Calculator
Turn retirement spending, personal savings and public income into a portfolio target and a possible date.
Open the tool →Monthly Budget Calculator
See what could make a monthly investing contribution sustainable alongside the rest of life.
Open the tool →How to Start Investing in Canada
Understand the goal, account, risk and cost decisions that sit behind a projection.
Read the guide →A projection shows the line. A review looks at what feeds it.
Contribution room, workplace matching, account order, tax and protection all affect what the line can mean. Want a second set of eyes on the whole picture? Your accounts, your coverage, and what happens next.
Reviews are with Sarah Lagrosa, licensed life and health insurance agent.