CD Calculator
Enter a deposit, a rate and a term to see what a certificate of deposit pays at maturity and what its APY is. You can also test an early-withdrawal penalty you choose.
Last updated November 3, 2026
From 1 to 120 months.
Your own assumption. Banks set their own penalty, so check your CD terms.
Result
Value at maturity = $10,407.42
| Result | Value |
|---|---|
| APY | 4.074% |
| Interest earned | $407.42 |
| Value at maturity | $10,407.42 |
The penalty is only the figure you entered; it is not a bank rule. Interest earned is before tax. FDIC insurance covers up to $250,000 per depositor, per bank, per ownership category.
Show the work
Formula: APY = G^12 − 1 and maturity value = deposit × G^months, where G = (1 + APR ÷ n)^(n ÷ 12) and n is the number of compounding periods per year.
- You entered $10,000.00 at 4% APR, compounded monthly, for 1 year (12 months).
- Growth factor per month: G = (1 + 4% ÷ 12)^(12 ÷ 12) = 1.00333333.
- APY = G^12 − 1 = 4.074%.
- Maturity value: $10,000.00 × G^12 = $10,407.42.
- Interest: $10,407.42 − $10,000.00 = $407.42.
Result: Value at maturity = $10,407.42
How the CD calculator works
APY = (1 + r ÷ n)^n − 1 and value = deposit × (1 + r ÷ n)^(n × t)
A CD pays a fixed rate for a fixed term. The rate r is the yearly rate as a decimal, n the number of times interest is compounded each year and t the term in years, which is the number of months divided by 12. The APY is the rate you effectively earn over one year once compounding is included.
Terms that are not whole years work the same way: the calculator grows the deposit by one monthly factor, G = (1 + r ÷ n)^(n ÷ 12), for each month of the term. Interest is the maturity value minus the deposit. This assumes you leave everything in the CD until maturity and the rate never changes.
See how we calculate for the formulas, sources and review schedule behind every calculator.
Also useful alongside this calculator: Loan Payment Calculator, Annuity Calculator and Retirement Calculator.
APY versus the stated rate
Banks must quote the APY so CDs can be compared on the same basis. Two CDs with the same 4% rate differ in APY if they compound differently: 4.000% annually, 4.060% quarterly, 4.074% monthly and 4.081% daily. When comparing offers, compare APY to APY.
Early-withdrawal penalties
Taking money out before maturity usually costs a penalty, commonly stated as a number of months of interest. Banks set their own rules, and some can reach into your principal. The calculator does not know your bank, so the penalty box is an assumption: it takes the months you enter times the simple monthly interest at your rate, deposit × rate ÷ 12.
On $10,000 at 4%, a 3-month penalty is $100. Subtracted from $407.42 of interest, that leaves $307.42. Read your CD agreement for the real terms before you rely on this figure.
Deposit insurance
CDs at FDIC-insured banks are covered up to the standard limit of $250,000 per depositor, per insured bank, per ownership category. Federally insured credit unions offer comparable NCUA coverage. Because the limit counts principal and interest together, large balances at one bank can be split across ownership categories or institutions.
Comparing several CDs
To compare offers, run each one with its own rate, term and compounding and look at the value at maturity. A longer CD with a higher APY is not automatically better: you give up access to the money for longer. Some savers split a deposit across several terms so part of it matures each year, which this calculator can model one CD at a time.
How term length affects the payout
At 4% compounded monthly, $10,000 is worth $10,201.67 after 6 months, $10,407.42 after 12 months, $10,831.43 after 24 months and $12,209.97 after 60 months. Longer terms lock in the rate for longer, which helps if rates fall and hurts if they rise.
General information, not financial advice
This calculator gives a general estimate from the numbers you enter. It is not financial or tax advice, and your actual results can differ. Check important decisions with a qualified professional or the official source.
Sources
Official and primary sources for the statements on this page. Their authors have not reviewed or endorsed this page.
- Consumer Financial Protection Bureau, Regulation DD, Appendix A to Part 1030, Annual Percentage Yield Calculation.. Gives the APY formula, 100 x [(1 + Interest/Principal)^(365/days in term) - 1].
- Federal Deposit Insurance Corporation, Understanding Deposit Insurance.. Says deposits, including certificates of deposit, are insured to at least $250,000 per depositor, per ownership category at each FDIC-insured bank.
- National Credit Union Administration, Share Insurance Coverage.. Says the NCUA Share Insurance Fund provides up to $250,000 of federal share insurance at federally insured credit unions.
How to use the CD Calculator
- Enter the amount you will deposit and the CD rate in percent.
- Enter the term in months and choose how often interest is compounded.
- Optionally enter an early-withdrawal penalty in months of interest.
- Read the APY and maturity value, open Show the work, then Copy, Print or Share.
Worked example
You deposit $10,000 in a 12-month CD at 4% compounded monthly. The APY is (1 + 0.04 ÷ 12)^12 − 1 = 4.074%. At maturity the CD is worth 10,000 × 1.0407415 = $10,407.42, so the interest is $407.42.
| Term | Value at maturity |
|---|---|
| 6 months | $10,201.67 |
| 12 months | $10,407.42 |
| 24 months | $10,831.43 |
| 60 months | $12,209.97 |
Frequently asked questions
What APY will my CD pay?
It depends on the bank, the term and the day you open it. Rates vary, so enter the rate you are offered and compare the APY the calculator shows with the bank’s quote.
Is the interest on a CD taxable?
In the United States, CD interest is generally taxable as ordinary income in the year it is credited, even if you cannot withdraw it. The results here are before tax.
What happens when a CD matures?
Most banks give a short grace period to withdraw or move the money. If you do nothing, many renew the CD automatically at the then-current rate.
Is the early-withdrawal penalty figure exact?
No. It is only the number of months you enter applied to simple interest. Your own bank decides the real penalty, so check the account terms.