FINANCIAL · CD APY

CD APY Calculator

Calculate the maturity value and interest earned on a certificate of deposit, or convert a nominal APR to APY based on compounding frequency.

CD Details
02 Result
Maturity value
$10,500.00
+$500.00 interest
Initial deposit$10,000.00
APY5.00%
Term365 days
Interest earned$500.00

About This Calculator

Calculate how much a certificate of deposit will be worth at maturity, or convert a bank's stated APR (annual percentage rate) to the actual APY (annual percentage yield) for easy comparison across offers.

How It Works

Choose CD Maturity mode to enter your deposit amount, advertised APY, and term. The calculator projects your final balance and total interest earned. Choose APY from APR mode to enter the nominal rate and compounding frequency — the calculator converts it to the true annual yield using the standard compounding formula.

The Formula

APY = (1 + APR/n)^n − 1 Maturity = Principal × (1 + APY)^(days/365)

APY
Annual Percentage Yield — the effective annual rate including compounding
APR
Annual Percentage Rate — the nominal (stated) rate before compounding
n
Compounding periods per year (e.g. 12 for monthly)
days
CD term length in days

Frequently Asked Questions

What is the difference between APR and APY?
APR is the nominal annual rate stated by the bank. APY reflects the actual return after accounting for how frequently interest is compounded. A 5% APR compounded monthly yields an APY of about 5.12% — the more frequent the compounding, the higher the APY relative to the APR.
How is CD maturity interest calculated?
The calculator uses the APY (not APR) and applies compound growth over the CD term expressed as a fraction of a year. A 12-month CD at 5% APY on $10,000 earns exactly $500 in interest, for a maturity value of $10,500.
Does the calculator account for early withdrawal penalties?
No. CD penalties for early withdrawal vary by institution and are not modeled here. Check your CD agreement for the penalty terms before withdrawing early.
Can I use this for high-yield savings accounts?
Yes. High-yield savings and money-market accounts quote APY, so use CD Maturity mode with the current APY and your expected balance. Note that savings-account rates can change, while a CD rate is locked in.