Finance

Compound Interest Calculator

Calculate compound interest, future value, total contributions, interest earned, and year-by-year investment growth.

Last updated July 9, 2026

Currency

Initial investment ($)

Contribution amount ($)

Contribution frequency

Interest rate (%)

Compounding frequency

Duration (years)

Future value

$300,851

$170,851 earned from interest

Contributions

$130,000

Interest earned

$170,851

Years projected

Growth over time

Contributions vs earnings

Contributions$130,000

Interest earned$170,851

YearStartAddedInterestEnd

1$10,000$6,000$919.19$16,919

2$16,919$6,000$1,419$24,339

3$24,339$6,000$1,956$32,294

4$32,294$6,000$2,531$40,825

5$40,825$6,000$3,148$49,973

6$49,973$6,000$3,809$59,782

7$59,782$6,000$4,518$70,299

8$70,299$6,000$5,278$81,578

9$81,578$6,000$6,094$93,671

10$93,671$6,000$6,968$106,639

Showing first 10 years of 20.

About This Tool

Use this compound interest calculator to estimate how an investment could grow with recurring contributions, different contribution frequencies, and daily, monthly, quarterly, or yearly compounding.

Compound Interest Formula

future value = P x (1 + r / n)^(n x t) plus recurring contributions

P is the starting principal, r is the annual interest rate, n is compounding periods per year, and t is time in years. Contributions are converted into an equivalent monthly amount for projection.

Examples

Long-term investing

$10,000 initial, $500 monthly, 7% return, 20 years

Result: Future value, contributions, interest earned, and year-by-year growth.

Contribution comparison

Monthly vs yearly contributions

Result: More frequent contributions start compounding sooner.

FAQ

Is the interest rate guaranteed?

No. The rate is an assumption for planning. Actual investment returns vary and can be negative.

How are contributions handled?

Contribution frequency is converted into an equivalent monthly contribution so the projection remains easy to compare across frequencies.

Does this include taxes or fees?

No. Reduce the assumed interest rate or contribution amount if you want to model fees, taxes, or inflation.

Important Note

Results are estimates for planning and education. They do not replace financial, tax, legal, or professional advice. Review assumptions before making decisions.

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