About this tool
Enter a starting amount, an annual interest rate, how long you will save for, how often interest compounds, and an optional monthly contribution. The calculator shows your projected balance, how much of it is money you put in, how much is interest earned, and a year-by-year table of the balance growing. It is an estimate for planning - real returns vary and it does not account for tax or inflation.
How to use it
- 1 Enter your starting balance (it can be zero).
- 2 Enter the annual interest rate as a percentage.
- 3 Set the number of years and how often interest compounds.
- 4 Optionally add a monthly contribution to see the effect of saving regularly.
Frequently asked questions
Does this include tax or inflation?
No. It is a gross projection. Your real, after-tax, inflation-adjusted result will be lower.
What does "compounding frequency" mean?
How often earned interest is added to the balance so it can itself earn interest. Monthly compounding grows slightly faster than annual for the same rate.
Is this financial advice?
No. It is a maths tool to illustrate compound growth.
Guide
Compound Interest Explained: How Small Monthly Savings Grow
The difference between simple and compound interest, why time matters more than the rate, and how a modest monthly habit turns into a large number.
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