About the CD Calculator
A CD calculator works out the maturity value of a certificate of deposit from the deposit, the APY, and the term. CDs trade liquidity for a guaranteed rate — you commit the money for a fixed period and the bank commits to the yield.
The formula
Maturity value = P · (1 + APY)^(months/12)APY is the annual percentage yield, already including compounding. The term is the fixed period you commit for, after which the CD matures and funds become available.
How to use this calculator
- 1Enter your Initial Deposit ($). The field starts at
10000, which you can overwrite. - 2Enter your Annual APY (%). The field starts at
5, which you can overwrite. - 3Enter your CD Term (Months). The field starts at
12, which you can overwrite. - 4Read the result straight away — it recalculates as you type, so there is no button to press. Use Share to copy a link that reopens the page with your exact numbers filled in.
Worked example
| Input | Value |
|---|---|
| Initial Deposit ($) | 10000 |
| Annual APY (%) | 5 |
| CD Term (Months) | 12 |
Result
Maturity Value: $10500.00
Interest Earned: $500.00
Average Monthly Interest: $41.67
Effective Monthly Rate: 0.4167%
Those are the values the page loads with, so you can reproduce this result yourself and then change one field at a time to see what drives the outcome.
Understanding your result
The trade is straightforward: you accept an early withdrawal penalty in exchange for a rate above ordinary savings, and unlike a savings account that rate cannot fall during the term. That protection is most valuable when rates are expected to decline, and least valuable when they are expected to rise.
A CD ladder resolves much of the liquidity problem. Splitting money across CDs maturing at staggered intervals means a portion becomes available regularly while most stays locked at longer, higher rates. It is the standard approach for holding a large cash position without either sacrificing yield or losing all access.
Things worth knowing
- Early withdrawal penalties are typically three to twelve months of interest. Check the exact terms before committing.
- A CD ladder gives regular access to part of your money while keeping most at longer-term rates.
- No-penalty CDs exist at slightly lower rates and can be worth the trade if your timeline is uncertain.
- Watch for automatic renewal. Many CDs roll over into a new term at whatever rate is then current unless you act.
- CDs are federally insured up to 250,000 dollars per depositor per bank in the US.
Frequently asked questions
What happens if I withdraw from a CD early?+
You pay a penalty, typically three to twelve months of interest depending on the term. On a short CD that can exceed the interest earned, leaving you with less than you deposited.
Are CDs better than savings accounts?+
They usually pay more but lock up your money. High-yield savings accounts sometimes match short CD rates while staying fully liquid, so compare current rates rather than assuming.
What is a CD ladder?+
Splitting your deposit across CDs with staggered maturities — say one, two, and three years. Something matures regularly, giving access to cash while most of the money earns longer-term rates.
Are CDs safe?+
Yes, within insurance limits — 250,000 dollars per depositor per bank through the FDIC in the US. The main risk is opportunity cost if rates rise while your money is locked in.