How do I calculate compound interest online for free?

Enter principal amount, annual interest rate, time period, and compounding frequency (daily/monthly/yearly). Click Calculate. See total amount, interest earned, and year-by-year growth. Free, no signup.

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📈 Compound Interest Calculator Online Free

Calculate compound interest and investment growth with year-by-year breakdown. Daily, monthly, quarterly, yearly compounding. No signup.

💵 Principal Amount

📊 Annual Rate (%)

📅 Time Period (Years)

🔁 Compounding

Compound Interest Calculator Online Free — See Your Money Grow

Our free compound interest calculator shows exactly how your investment grows over time with the power of compounding. Enter principal, rate, time, and compounding frequency to see total amount, interest earned, and year-by-year growth table.

Compound Interest Formula

A = P(1 + r/n)^(nt)
A = Final amount, P = Principal, r = Annual rate (decimal), n = Compounding per year, t = Years

Simple vs Compound Interest

Simple Interest: Interest on principal only — linear growth
Compound Interest: Interest on principal + accumulated interest — exponential growth

Rule of 72

Divide 72 by annual interest rate to estimate years to double money. At 8% rate: 72÷8 = 9 years to double. At 12% rate: 72÷12 = 6 years to double.

Compounding Frequency Impact

Daily compounding gives slightly higher returns than monthly, which beats quarterly, which beats yearly. The difference grows significantly over long periods.

How to Use the Compound Interest Calculator

Enter the principal amount you are starting with
Enter the annual interest rate
Enter the time period in years and choose a compounding frequency
Click Calculate to see the total amount, interest earned, and year-by-year growth

Frequently Asked Questions

How do I calculate compound interest online?

Enter principal, rate, time, frequency, click Calculate. See total amount, interest earned, year-by-year table. Free.

What is the compound interest formula?

A = P(1 + r/n)^(nt). A=Final amount, P=Principal, r=Annual rate, n=Compounding frequency, t=Years.

What is the difference between simple and compound interest?

Simple interest: only on principal. Compound interest: on principal + accumulated interest. Compound grows exponentially.

How does compounding frequency affect returns?

Daily > Monthly > Quarterly > Yearly. More frequent compounding = higher returns over time.

What is the Rule of 72?

Divide 72 by interest rate to find years to double money. At 8%: 72÷8 = 9 years to double.