CD Calculator (Certificate of Deposit)
Calculate exactly how much your certificate of deposit will earn at maturity, compare APY across compounding frequencies, and estimate early withdrawal penalties. Pre-loaded with example data — try it now!
🚀 Quick Start Examples
Key Values
- Total Interest
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- Effective APY
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- After-Tax Interest
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- Monthly Avg Earnings
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Interpretation
Early Withdrawal Penalty
Typical penalty if withdrawn early:
- Terms ≤ 12 mo (3 mo interest)
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- Terms > 12 mo (6 mo interest)
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Balance Growth Over Term
Compare Terms at Your Rate
| Term | Maturity Value | Interest Earned |
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How CD Interest Works
A certificate of deposit (CD) is a time deposit: you agree to leave your money with a bank for a fixed term, and in exchange the bank pays a higher, guaranteed interest rate than a regular savings account. Your maturity value is calculated with compound interest:
where r = annual rate, n = compounding periods/year, t = years
APY vs. rate: Banks advertise APY (Annual Percentage Yield) because it includes compounding. A 5.00% rate compounded daily gives 5.13% APY. When comparing CDs, always compare APY to APY.
Early withdrawal penalties: Withdrawing before maturity typically costs 3 months of interest for terms of 12 months or less, and 6 months of interest for longer terms (varies by bank). This calculator estimates both so you can weigh liquidity risk.
CD laddering: Instead of one 5-year CD, split your deposit across 1—5 year maturities. Every year one CD matures, giving you access to cash or the option to reinvest at current rates. This balances yield and flexibility.
Taxes: CD interest is taxed as ordinary income in the year it is credited, even if you don't withdraw it. Enter your marginal tax bracket above to see after-tax earnings.
Frequently Asked Questions
How is CD interest calculated?
Compound interest: Maturity = Deposit × (1 + rate/n)^(n×years). Most banks compound daily and credit monthly. Enter your bank's stated rate and compounding, and this calculator handles the math.
Is APY better than the interest rate for comparing CDs?
Yes. APY includes compounding, so it reflects what you actually earn. Two CDs with the same rate but different compounding have different APYs.
Are CDs safe?
CDs at FDIC-member banks are insured up to $250,000 per depositor per bank. Credit union CDs have equal NCUA coverage. Your principal and accrued interest within the limit cannot be lost.
What happens when my CD matures?
Most banks give a 7–10 day grace period to withdraw or change terms. If you do nothing, the CD usually auto-renews at the bank's current rate — which may be much lower than a promotional rate, so set a reminder.
Should I choose a CD or a high-yield savings account?
Choose a CD when you won't need the money before maturity and want a locked rate. Choose high-yield savings for emergency funds and money you may need anytime — the rate is variable but the money is liquid.