CD Calculator: APY & Interest Earnings

Calculate how much a certificate of deposit (CD) will earn at maturity from either an advertised APY or a nominal interest rate and compounding schedule.

Maintained by Archie Chang · Rate data checked October 2, 2026 · Methodology & sources

Splitting savings across several maturity dates? Use the CD ladder calculator to compare the deposit and first-term interest for each CD.

Not financial advice. This calculator provides estimates for informational and educational purposes only. Results are not a loan offer or a guarantee of terms. Always confirm figures with a qualified lender or financial advisor before making decisions.

CD Details

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%

APY already includes the bank’s compounding frequency, so it is not compounded a second time.

Maturity Value

$10,173.00

Deposit (Principal)$10,000
Total Interest Earned$173.00
APY Used1.73%
Total at Maturity$10,173

FDIC National Deposit Rates

CD Early Withdrawal Penalty CalculatorCD Ladder Calculator
1-Year CD1.73%
5-Year CD1.38%

As of September 21, 2026. These are national rates, not top-yield offers. View the FDIC table.

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CD Early Withdrawal Penalty CalculatorCD Ladder CalculatorMortgage CalculatorStudent Loan CalculatorCurrent Fed Rate

Frequently Asked Questions About CD Rates

How do I calculate CD interest?

Enter your deposit amount (principal), the APY quoted by the bank, and the term length. Because APY already includes compounding, the calculator applies A = P(1 + APY)^t, where P is the principal and t is the term in years. The result is the estimated maturity value if the CD is held for the full term.

What is the difference between APY and interest rate on a CD?

The interest rate is the nominal annual rate before compounding is applied. APY (Annual Percentage Yield) already factors in how often interest compounds, so it reflects what you earn over a year. Use APY mode when your institution quotes APY; use interest-rate mode only when you need to convert a nominal rate and compounding schedule.

When does CD compounding frequency matter?

Compounding frequency matters when you enter a nominal interest rate. The calculator converts that rate to APY using the selected daily, monthly, quarterly, or annual schedule. If you enter an advertised APY, compounding is already included and the calculator does not apply it again.

What happens if I withdraw from a CD early?

Most CDs charge an early withdrawal penalty, commonly a forfeiture of a set number of months of interest (for example, 3 months of interest on a 1-year CD, or 6-12 months on longer terms). This calculator shows the interest you would earn if you hold the CD to maturity; it does not model early withdrawal penalties, since those vary significantly by bank and CD term.

Is CD interest taxable?

Yes. Interest earned on a CD held outside a tax-advantaged account (like an IRA) is taxable as ordinary income in the year it is earned or credited, even if you do not withdraw it, and the bank will issue a Form 1099-INT once interest for the year exceeds $10. This calculator shows pre-tax interest; consult a tax professional for how it affects your specific return.

How much will a $10,000 CD earn in a year?

It depends on the APY offered. At the FDIC's September 21, 2026 national 12-month CD deposit rate of 1.73%, a $10,000 CD would earn about $173 over one year if held to maturity. This FDIC figure is a deposit-weighted national rate, not a claim about the best offer available. Enter the APY quoted by your institution for a relevant estimate.

Are CD rates tied to the Federal Reserve rate?

CD rates are not set directly by the Fed, but banks typically move CD APYs up or down in the same direction as the federal funds rate over time, since it affects banks' own cost of funds and what they are willing to pay to attract deposits. CD rates react more slowly and less precisely than fed-funds-linked products like savings accounts, and shorter-term CDs tend to track short-term rate expectations more closely than long-term CDs. See our current Fed rate and next FOMC meeting pages to track the rate environment.

How It's Calculated

A bank's advertised APY already reflects compounding. When APY is selected, the calculator applies that effective annual yield once over the selected term:

A = P · (1 + APY)t

If you enter a nominal interest rate, the calculator first converts it to APY with APY = (1 + r/n)n − 1, where r is the annual nominal rate and n is the number of compounding periods per year. The maturity-value formula then uses that calculated APY.

Where each term means:

  • A — the maturity value: your deposit plus all interest earned by the end of the term.
  • P — the principal: the amount you deposit into the CD.
  • APY — the quoted Annual Percentage Yield as a decimal. A 4.5% APY becomes 0.045.
  • t — the term length in years. An 18-month CD is t = 1.5.

A worked example

Suppose you deposit $10,000 into a 1-year CD at 5% APY:

  • P = 10,000
  • APY = 5% = 0.05
  • t = 1 year

Plugging these into the formula gives A = 10,000 · (1 + 0.05)1 = $10,500. That is $500 in total interest over the year. The APY already accounts for the institution's compounding method.

Note: this calculation assumes the CD is held to maturity. It does not include early withdrawal penalties or taxes on interest earned. Actual APYs vary by bank, term, and deposit amount.

Authoritative sources: FDIC national CD rates · CFPB APY calculation rules · IRS interest income guidance