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Compound Interest Calculator

Calculate compound interest and investment growth with additional contributions

Free to use, no watermarks, runs in your browser—nothing uploads to our servers

Initial Principal ($)

Annual Interest Rate (%)

Time Period (Years)

Compounding Frequency

Additional Contribution (per period) ($) Optional

Report a bug

If this tool misbehaves, share a quick summary so we can investigate. We include the tool URL automatically—no need to copy and paste.