Savings

Compound Interest Calculator

Estimate how savings or investments can grow over time with monthly contributions and compounding.

Starting amount

Monthly contribution

Annual return

Use a planning estimate, not a guaranteed return.Years

Estimated future balance

$170,619

$100,619 estimated growth over 20 years.

Total contributions

$70,000

Includes starting amount plus monthly contributions.

Eerns calculators are for educational estimates only and are not financial, tax, legal, or investment advice. Results depend on the information entered and may not reflect a full situation.

How to use it

Use this calculator to estimate how a starting balance, recurring contributions, time, and an annual return could affect long-term growth.

Calculation method

The calculator compounds monthly. Each month, it applies the estimated monthly return and then adds the monthly contribution.

Important limitation

Investment returns are not guaranteed. Fees, taxes, inflation, and market changes are not included.

Example scenario

For example, a $10,000 starting amount with $250 added monthly for 20 years at a 7% annual return shows the difference between total contributions and estimated growth.

Embed version

Choose an embed theme.

Each embed URL can include a brightness, top-bar color, and main-area color. This makes it easier to match the tool to another website.

Embed theme

Default professional blue header with a white calculator area.

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Common questions

Frequently asked questions

What does compound interest mean?

Compound interest means growth is calculated on both the original balance and prior growth. Over long periods, that can make time and consistency very important.

Does this calculator guarantee an investment return?

No. The annual return is only a planning assumption. Actual returns can be higher or lower and may include taxes, fees, inflation, and market changes.

Should I enter a monthly contribution?

Enter a monthly contribution if you plan to keep adding money over time. Leave it at zero if you only want to estimate growth on a starting amount.

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