A certificate of deposit locks one deposit at one rate for a fixed term. Enter the amount, the APY and the term in months to see what the CD is worth at maturity and how much of that is interest. The table below compares terms at the same APY; the last section estimates what an early withdrawal costs.
Months
Months. Leave blank to skip the early-withdrawal estimate.
Months of interest
| Term | Value | Interest |
|---|
The table above holds the APY and deposit fixed and varies only the term. At 4.00% APY on $10,000.00: 3 months is worth $10,098.53 ($98.53 interest), 12 months is worth $10,400.00 ($400.00), and 60 months is worth $12,166.53 ($2,166.53).
A CD's APY already contains its compounding, so the value at maturity is a single step: value = deposit × (1 + APY)^(months ÷ 12). There is no separate compounding-frequency input in APY mode because the frequency is already priced into the APY.
Interest does not scale in a straight line with the term, because the earlier interest keeps compounding. Eighteen months is not 1.5 × the 12-month interest: 1.5 × $400.00 would be $600.00, but the actual 18-month figure is $605.96, because the first 12 months of interest are themselves earning interest during months 13–18.
The estimate accrues interest up to the withdrawal month, then subtracts a penalty equal to a number of months of interest on the deposit — the same shape most banks use, though the exact rule and the exact rate it applies to comes from your CD's disclosure, not this calculator.
On the default $10,000.00, 4.00% APY, 12-month CD: withdrawing after 8 months with a 3-month penalty leaves $264.92 accrued against a $100.00 penalty, for $164.92 of net interest and $10,164.92 received. Withdraw after only 2 months and the $100.00 penalty exceeds the $65.58 accrued, so $34.42 comes out of the deposit itself rather than only the interest.
A CD takes one deposit at a fixed rate for a fixed term, with a penalty for touching it early. A savings account takes ongoing deposits at a rate the bank can change any time, with no penalty for withdrawing. If you are adding money every month, the savings account interest calculator matches how that account is quoted and paid.
To compare compounding frequencies directly rather than working from an APY, use the daily compound interest calculator . Neither page compares rates across banks or recommends a product — enter your own numbers to see what they produce.
The APY is applied to the deposit for the length of the term: value = deposit × (1 + APY)^(months ÷ 12). $10,000.00 at 4.00% APY is worth $10,400.00 after 12 months and $10,605.96 after 18. The compounding schedule is already inside the APY, which is why two CDs with the same APY pay the same regardless of how often each one compounds.
At 4.00% APY: $198.04 in 6 months, $400.00 in 12 months, $816.00 in 24 months and $2,166.53 in 60 months. At 4.50% APY the 60-month figure is $2,461.82, so a half-point rate difference is worth about $295 over five years on this deposit.
The interest rate is the nominal figure before compounding; APY is what you actually earn in a year. A 4.00% rate compounded daily is a 4.0808% APY, and compounded monthly a 4.0742% APY. Compare CDs by APY and enter the APY here in the default mode.
Most banks charge a penalty equal to a set number of months of interest. On a 12-month, $10,000.00 CD at 4.00% withdrawn after 8 months with a 3-month penalty, you have accrued $264.92 and give back $100.00, so you leave with $164.92 of interest. After only 2 months the $100.00 penalty exceeds the $65.58 accrued and $34.42 comes out of your deposit. Your CD's disclosure states the exact rule.
Most CDs take a single deposit when they are opened, which is why this calculator has no monthly deposit field. If you are saving into an account month by month, use the savings account interest calculator instead.
Enter the APY, a starting balance and a monthly deposit to get a month-by-month statement.
Interest per day on any balance, plus the total accrued over any number of days.
Calculate daily compound interest with contributions and see year-by-year growth and APY.