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CD Interest Calculator

Enter your deposit amount, the APY your bank is offering, and the term in months to see your maturity value and total interest earned. The result updates as you type, and everything stays in your browser.

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Maturity value--
Interest earned--
Effective annual yield--

Enter your figures above. Results update live and stay in your browser.

Jessica Martinez
By Jessica Martinez, Contributing Writer, Business & Finance
Updated June 20, 2026

Compare multiple CD rates side by side

Use the CD Rate Calculator to enter up to four different APYs and terms at once and see which combination earns the most.

Open the CD Rate Calculator →

How CD interest is calculated

A certificate of deposit earns compound interest on a fixed deposit for a fixed term. The maturity value formula is: A = P x (1 + r/n)^(n x t), where P is your deposit, r is the annual rate (APR), n is the number of compounding periods per year, and t is the term in years. Because banks quote the APY rather than the APR, the calculator works backward to find the equivalent APR and then applies the compounding formula.

APY vs. APR on a CD. The APY you see advertised already bakes in the effect of compounding. A 5.00% APY compounded daily is slightly different from 5.00% APY compounded monthly, but both pay you exactly 5.00% on your balance over a full year. When comparing CDs across banks, compare APYs, not APRs.

Quick reference: what common APYs earn on a $10,000 deposit

APY3 months6 months12 months
4.00%$99$198$400
4.50%$112$224$450
5.00%$124$247$500
5.25%$130$260$525

Figures rounded to the nearest dollar, assuming daily compounding. Use the calculator above for your exact numbers.

CD basics worth knowing

A CD is a time deposit insured by the FDIC (or NCUA at credit unions) up to $250,000 per depositor per institution. You agree to leave the money on deposit for the stated term. Early withdrawal carries a penalty, typically 90 to 180 days of interest on shorter terms and up to 12 months of interest on longer ones. That penalty can eat into principal on very short terms withdrawn early, so read the disclosure before you open the account.

CD interest is taxable as ordinary income in the year it is credited, even if you do not pull the money out. Your bank will issue a Form 1099-INT for any year in which you earn $10 or more. Holding a CD inside a traditional IRA or Roth IRA defers or eliminates that tax bill, depending on the account type.

Thinking longer term?

The Investment Calculator shows how contributions plus compound returns stack up over many years, beyond what a single CD term covers.

Open the Investment Calculator →

This tool is informational and educational. It is not financial advice, and deposit rates change frequently. Verify current rates directly with the institution before opening an account.

Jessica Martinez
About the author
Jessica Martinez
Contributing Writer, Business & Finance, Encore Editorial

A reformed credit analyst, Jessica Martinez turns dense financial paperwork into something you can actually use. She writes the explainers behind these calculators and checks every formula against a primary source before it ships.

Good to know

FAQs

How much will $10,000 make in a 6-month CD?

At a 5.00% APY, a $10,000 six-month CD earns roughly $247 in interest, returning $10,247 at maturity. At 4.00% APY the interest drops to about $198. The exact figure depends on the compounding frequency and the precise APY. Enter your actual numbers in the calculator above for the exact result.

How much does a $100,000 CD make in a year?

At 5.00% APY, a $100,000 one-year CD earns $5,000 in interest. At 4.50% APY it earns $4,500, and at 4.00% APY it earns $4,000. Because APY already accounts for compounding, you can estimate by multiplying the deposit by the APY for a full year. Use the calculator for the exact figure on any term.

What is the difference between CD APY and CD APR?

APR is the stated annual rate before compounding. APY is the effective rate after compounding is applied. Under the Truth in Savings Act, banks must disclose the APY on deposit accounts, so that is the number to use when comparing offers. A higher compounding frequency (daily vs. monthly) produces a slightly higher APY from the same APR.

How is CD interest compounded?

Most banks compound CD interest daily or monthly, though quarterly and annual compounding also exist. Daily compounding produces marginally more interest than monthly compounding at the same stated rate. The disclosed APY accounts for the compounding frequency, so comparing APYs across banks gives a fair comparison regardless of how each bank compounds.

Is CD interest taxable?

Yes. Interest credited to a CD is taxable as ordinary income in the year it is credited, even if you leave it in the account and do not make a withdrawal. Banks issue Form 1099-INT for any calendar year in which you earn $10 or more in interest. Holding a CD inside an IRA can defer or eliminate the tax, depending on the account type. Consult a tax professional for guidance on your situation.