Compound interest calculator
Watch your savings grow as interest earns interest, with a table for every year.
- 100% free
- No sign-up
- Runs in your browser
How to use Compound interest calculator
- Enter your savings
- Choose the timing
- Read the result
Your savings
Final balance
Enter a starting amount or a regular deposit, the interest rate and the number of years.
Next: Retirement calculator · Inflation calculator · ROI calculator
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How to use Compound interest calculator
Enter your savings
Type a starting amount, a regular deposit if you make one, the yearly interest rate and the number of years.
Choose the timing
Pick how often interest is compounded, how often you deposit, and whether deposits come at the start or end of each period.
Read the result
See the final balance, what you put in and the interest earned, then follow the growth year by year.
Why use Utils365
Regular deposits included
Weekly, fortnightly, monthly, quarterly or yearly deposits, at the start or end of each period, as your bank does it.
Any compounding
Daily, monthly, quarterly or yearly compounding, with the effective yearly rate (APY) it gives.
Rising deposits
Raise your deposit by a percentage each year to see the effect of saving more as your pay grows.
Private and free
It all runs in your browser. No sign-up and nothing you type is sent anywhere.
Frequently asked questions
What is the compound interest formula?
A = P × (1 + r ÷ n)^(n × t), with P the starting amount, r the yearly rate, n the compounding periods a year and t the years. 10,000 at 5% compounded monthly grows to 16,470.09 in 10 years.
How do regular deposits change the result?
Each deposit starts earning interest of its own. Adding 100 a month to that 10,000 at 5% for 10 years brings the total to 31,998.32: 22,000 paid in and almost 10,000 in interest.
Does compounding daily make much difference?
Less than you might think. 5% compounded yearly is 5% a year; monthly is 5.12% and daily 5.13%. The rate and the time matter far more.
What is the difference between deposits at the start and end?
A deposit at the start of a period earns interest for that period; one at the end doesn’t. Over years, start-of-period deposits end up slightly higher.
What is the rule of 72?
A shortcut for doubling time: divide 72 by the yearly rate. At 6% money doubles in about 12 years; at 8% in about 9.
Is the interest rate the same as the return?
For a savings account, yes. For shares or funds the return changes every year, so treat any fixed rate as an average and the result as an estimate.