Introduction
A CD (certificate of deposit) is a type of savings account where you lock your money away for a set period of time. In return, the bank pays you a fixed interest rate that is usually higher than a regular savings account. The APY, or annual percentage yield, tells you how much your money truly earns in one year after compounding is factored in.
This CD APY calculator helps you find out exactly how much your CD will be worth when it matures. Enter your deposit amount, interest rate, compounding frequency, and term length, and the tool does the rest. It shows your total balance at maturity, the interest you earn, and a full step-by-step breakdown of the math. You can also add your tax rate to see your after-tax earnings.
Whether you are comparing CD rates from different banks or just want to know how much interest a CD will pay, this calculator gives you clear and accurate results in seconds.
How to Use Our CD APY Calculator
Enter a few details about your certificate of deposit below. The calculator will show your effective APY, total interest earned, and your full balance at maturity.
Initial Deposit: Type the dollar amount you plan to put into the CD. This is the money you give the bank when you open the account.
Annual Interest Rate: Enter the yearly interest rate the bank offers on the CD. This is the stated rate before compounding is applied. If you need help understanding how your stated rate translates to what you actually earn, our APY to APR calculator can clarify the difference.
Compounding Frequency: Pick how often the bank adds interest to your balance. Common choices are daily, monthly, or quarterly. More frequent compounding means a slightly higher APY. To explore how compound interest works across different account types, try our dedicated tool.
CD Term: Enter how long your money will stay in the CD. Use the Years and Months fields to set the exact length. For example, an 18-month CD would be 1 year and 6 months.
Marginal Tax Rate: Enter your combined federal and state tax rate if you want to see after-tax results. CD interest is taxed as regular income. If you are unsure of your rate, our tax bracket calculator can help you find it. Leave this at 0% if you only want to see pre-tax numbers.
Click Calculate to see your results, step-by-step math, charts, and a full accumulation schedule. Click Reset to clear your entries and start over.
What Is a CD APY Calculator?
A CD APY calculator helps you find out how much money you will earn when you put your savings into a certificate of deposit. A certificate of deposit (CD) is a type of savings account you open at a bank or credit union. You agree to leave your money in the account for a set amount of time, called the term. In return, the bank pays you a fixed interest rate that is usually higher than a regular savings account. For a broader look at CD earnings including different term comparisons, see our CD calculator.
What Does APY Mean?
APY stands for annual percentage yield. It tells you how much your money actually grows in one year after compounding is included. Compounding means the bank adds interest to your balance, and then you start earning interest on that interest too. The more often a bank compounds your interest — daily, monthly, or quarterly — the more you earn. APY takes all of that into account, so it gives you a true picture of your earnings. You can use our APY calculator to quickly convert any nominal rate into an effective annual yield.
How a CD Works
When you open a CD, you deposit a lump sum of money. You cannot add more money or withdraw it until the term ends without paying a penalty. CD terms can be as short as one month or as long as ten years. When the term ends, your CD matures, and you get back your original deposit plus all the interest it earned. If you want to project what that final payout will be worth, our future value calculator can help with longer-range planning.
APY vs. Interest Rate: What's the Difference?
Banks often show two numbers: the interest rate and the APY. The interest rate is the base rate the bank uses to calculate your earnings. The APY is always equal to or higher than the interest rate because it includes the effect of compounding. When you compare CDs from different banks, always compare APY to APY. That way you see which one truly pays more. Our APR calculator can also help you understand how stated rates work across different financial products.
Why Compounding Frequency Matters
A CD that compounds daily will earn slightly more than one that compounds monthly, even if both have the same interest rate. This is because daily compounding adds interest to your balance more often, so your money grows a tiny bit faster. The difference is small on short terms and low balances, but it adds up over time and with larger deposits. Our daily compound interest calculator lets you see exactly how much extra you earn with daily compounding compared to less frequent options.
Taxes on CD Interest
Interest earned on a CD is taxable income. The IRS treats it as ordinary income, which means you pay your regular income tax rate on it. If you enter your tax rate into this calculator, it will show you how much of your interest you keep after taxes. This helps you understand your real earnings. For a full picture of how your CD interest fits into your overall tax situation, try our income tax calculator. You may also want to compare CD returns against a high-yield savings account or explore building an overall savings plan to see which option best fits your financial goals.