Simple & Compound Interest Calculator
Compare simple vs compound interest growth on your investment, with a chart and year-by-year table.
Runs in your browser. Nothing is uploaded.Simple & Compound Interest Calculator in 3 steps
Enter your investment details
Add the principal, annual interest rate and time period in years.
Choose a compounding frequency
Annually, semi-annually, quarterly, monthly or daily — more frequent compounding grows faster.
Compare the results
See simple vs compound totals side by side, a growth chart, and a year-by-year breakdown.
Why use this Simple & Compound Interest Calculator
Questions about this tool
What is the difference between simple and compound interest?
Simple interest is calculated only on the original principal every period, so it grows in a straight line. Compound interest is calculated on the principal plus all previously earned interest, so it grows faster and faster over time — the "extra from compounding" shows exactly how much more you'd earn.
Why does compounding frequency matter?
More frequent compounding (daily vs annually, for example) means interest starts earning its own interest sooner, which produces a slightly higher total return even at the same stated annual rate.
Is this the same as how a bank savings account works?
Most savings accounts and fixed deposits use compound interest, often compounded quarterly or monthly — check your specific account's terms for the exact frequency used.
Does this account for taxes or inflation?
No, this shows pure nominal interest growth on your principal — actual real-world returns would need to account for any applicable taxes and the effect of inflation on purchasing power.