Free compound interest calculator
Enter what you have now, what you add regularly, the yearly return and how long you will let it grow. You will see the final balance, how much of it is your own money and how much is interest, year by year.
Free, no sign-up. Everything is worked out in your browser: nothing you type is sent or stored.
How compound interest works
With simple interest you earn interest only on the money you put in. With compound interest you also earn interest on the interest you have already earned, so growth speeds up over time. The formula for a single deposit is balance = amount × (1 + rate ÷ n)n × years, where n is how many times a year interest is compounded.
Regular contributions add to the effect. This calculator adds your contribution at each period and grows the balance by the interest earned between contributions, so contributions made at different frequencies than the compounding still work out exactly.
Use it for TFSA, RRSP and other accounts
The calculator does not know which account you use, and it ignores fees and tax, so treat the result as a before-tax, before-fee estimate. In a registered account such as a TFSA or RRSP, growth is sheltered from tax, so the number is closer to your result than in a taxable account. Real returns change from year to year; try several rates, for example 3%, 5% and 7%, to see a range.
Frequently asked questions
What is a good interest rate to use?
It depends on where the money is. A high-interest savings account pays much less than a diversified investment portfolio, which has historically returned more with more ups and downs. Try a low, a middle and a high rate to see a range.
What does "in today's money" mean?
Prices rise over time, so a dollar in 20 years buys less than a dollar today. The inflation setting shows what your future balance would be worth in today's purchasing power.
Are contributions made at the start or the end of each period?
You can choose. Contributions at the start of the period earn interest for one more period, so the balance is a little higher.
Read the guides
Track the real numbers
In Budget Dashboard you can set savings goals, see how much you really save each month from your bank transactions and check your progress in the yearly review. It is free and your data stays in your browser.
Open the free Budget Dashboard
More free calculators
- Savings goal calculator – How much to save each month to reach a goal by a date, or how long it takes at your pace.
- Emergency fund calculator – How much to keep for emergencies (3 to 12 months of essentials) and how long it takes to build.
- Debt payoff calculator – Compare the debt avalanche and the debt snowball and see your debt-free date and interest saved.
These calculators give estimates for planning and learning. They are not financial, tax or legal advice, and real lenders, banks and tax rules can differ. Check the numbers with your lender or a qualified professional before you decide.
Published by Budget Dashboard. Questions or corrections? Contact us.