Compound Interest Calculator
How to use the Compound Interest Calculator
- Enter your starting principal (the amount you invest or save).
- Enter the annual interest rate as a percentage (e.g. 5 for 5%).
- Enter how many years the money will compound.
- Set compounds per year (12 for monthly, 4 for quarterly, 1 for annually).
- Review future value and interest earned — all math runs locally in your browser.
Why calculate locally?
Your inputs for Compound Interest Calculator are processed entirely in browser memory. Financial and personal numbers are never sent to a server, stored in a database, or retained after you close the tab. This makes local calculation ideal for sensitive payroll, pricing, and business data.
Frequently asked questions
What formula does this use?
Future value = principal × (1 + r/n)^(n×t), where r is the annual rate as a decimal, n is compounds per year, and t is years.
What should I enter for compounds per year?
Use 1 for annual, 4 for quarterly, 12 for monthly, or 365 for daily compounding. Monthly (12) is a common default for savings accounts.
Are my investment numbers uploaded?
No. All calculations run 100% client-side in your browser. Your numbers never leave your device.
Is this Compound Interest Calculator free?
Yes. Every calculator on calculate.logicapplabs.com is free to use with no account required.