APY Calculator

Q: What is the difference between APY and interest rate?

The interest rate is the nominal annual rate. APY (annual percentage yield) includes the effect of compounding over a year, so it helps compare offers with different compounding schedules.

Q: How do you convert interest rate to APY?

For n compounding periods per year, APY = (1 + r/n)^n − 1, where r is the nominal annual rate as a decimal. This page does that conversion for you.

Q: Can I convert APY back to an interest rate?

Yes. Given APY and compounding frequency n, the equivalent nominal rate is r = n × ((1 + APY)^(1/n) − 1). Results are illustrative—confirm figures with your institution.

Q: Does this show live CD rates?

No. You type the numbers. Free CD Calculator is not a bank and does not quote live rates or open accounts.

Convert a nominal interest rate to APY, or APY back to an equivalent interest rate, for a compounding frequency you choose. Useful when a CD quote shows one figure and you need the other.

Rate ↔ APY

Convert

Rate → APY APY → Rate

Interest rate (nominal)

Compounding frequency Match the compounding on the disclosure when you can.

Result

APY

4.50%

Interest rate

4.40%

APY

4.50%

Not a live bank quote. Confirm APY, compounding, and early-withdrawal terms with your institution.

Estimating CD maturity value? Use the CD calculator.

How it works

Choose Rate → APY or APY → Rate.
Enter the known percentage and pick compounding (daily, monthly, quarterly, or annually).
Read the converted figure. Both rate and APY are shown so you can double-check.

Formula notes

With n compounding periods per year and nominal rate r (as a decimal): APY = (1 + r/n)ⁿ − 1. Solving for rate: r = n × ((1 + APY)^1/n − 1).

These formulas are standard illustrations for comparing quotes. Banks may use specific day-count methods. This page does not open accounts or display live rates.

FAQ

What is the difference between APY and interest rate?

The interest rate is the nominal annual rate. APY already includes the effect of compounding over a year, so it helps compare offers with different compounding schedules.

How do you convert interest rate to APY?

For n compounding periods per year, APY = (1 + r/n)ⁿ − 1, where r is the nominal annual rate as a decimal.

Can I convert APY back to an interest rate?

Yes. Given APY and compounding frequency n, r = n × ((1 + APY)^1/n − 1). Confirm figures with your institution.

Does this show live CD rates?

No. You type the numbers. This site is not a bank and does not quote live rates or open accounts.