guide
How CD interest is calculated
See how deposit, APY, and term determine maturity value.
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Free certificate of deposit calculator
CD calculator
Estimate a certificate of deposit's balance at maturity, see how interest builds, and compare a second offer without sending your numbers to a server.
01
Enter the CD details
02
Estimated maturity value
First CD offer
Opening deposit
Interest earned
APY
Term
Opening depositInterest
03
Compare the offers
Different terms lock your money for different lengths of time. A larger maturity value does not by itself make an offer a better fit.
| Offer | APY | Term | Interest | Maturity value |
|---|
04
Interest milestones
The first offer is shown at opening, each full year, and maturity.
| Milestone | Balance | Interest earned |
|---|
Understand the estimate
How this CD calculation works
The calculator treats the advertised APY as the effective annual return, including compounding. For a term measured in months, it uses maturity value = deposit × (1 + APY)^(months / 12). Interest earned is the maturity value minus the opening deposit.
Most standard CDs accept one opening deposit and hold it until maturity. This estimate assumes the APY stays fixed and all interest remains in the CD. It excludes taxes, fees, early-withdrawal penalties, promotional conditions, callable or brokered CDs, and institution-specific rounding.
A CD usually restricts access to the money for a stated term, and withdrawing early may trigger a penalty. Compare the term, APY, minimum deposit, penalty, renewal rules, and insurance coverage in the institution's disclosure before opening an account. Read the Consumer Financial Protection Bureau's CD overview.
Need recurring deposits instead? Use the savings goal calculator. For a general growth projection, use the compound interest calculator.
Worked example
Estimate a one-year CD
Enter a $10,000 opening deposit, 4% APY, and a 12-month term. With the interest left in the account, the estimated maturity value is $10,400 and the estimated interest is $400.
Try this example in the calculatorCommon questions
Frequently asked questions
What is a CD maturity value?
It is the opening deposit plus the estimated interest accumulated through the end of the stated term.
What is the difference between APY and an interest rate?
APY expresses the effective annual yield after compounding. A nominal interest rate may not include the effect of compounding.
Does this estimate include early-withdrawal penalties?
No. Penalties vary by institution and product. Review the account disclosure before opening or closing a CD.
Can I add money to the CD every month?
This calculator models a standard CD funded with one opening deposit. Use the savings goal or compound interest calculator for recurring deposits.
Is the higher maturity value always the better CD?
No. A longer term can produce a larger balance while restricting access to the money for more time. Compare term, penalties, minimums, renewal rules, and insurance coverage.