1. Enter deposit and rate
Choose APY when the bank quotes annual percentage yield, or nominal rate when the contract specifies a compounding frequency.
Savings
CD calculator
Estimate a certificate of deposit maturity value using APY or a nominal rate, and model recurring deposits, withdrawals, interest payouts and tax.
Total value received
$10,500.00
Net interest
$500.00
Gross interest
$500.00
Estimated tax
$0.00
Total deposited
$10,000.00
Total withdrawn
$0.00
Effective annual rate
5%
Deposit schedule
Monthly opening balance, cash flows, interest and ending balance.
| Month | Starting balance | Deposit | Withdrawal | Interest | Balance |
|---|---|---|---|---|---|
| 1 | $10,000.00 | $0.00 | $0.00 | $40.74 | $10,040.74 |
| 2 | $10,040.74 | $0.00 | $0.00 | $40.91 | $10,081.65 |
| 3 | $10,081.65 | $0.00 | $0.00 | $41.07 | $10,122.72 |
| 4 | $10,122.72 | $0.00 | $0.00 | $41.24 | $10,163.96 |
| 5 | $10,163.96 | $0.00 | $0.00 | $41.41 | $10,205.37 |
| 6 | $10,205.37 | $0.00 | $0.00 | $41.58 | $10,246.95 |
| 7 | $10,246.95 | $0.00 | $0.00 | $41.75 | $10,288.70 |
| 8 | $10,288.70 | $0.00 | $0.00 | $41.92 | $10,330.62 |
| 9 | $10,330.62 | $0.00 | $0.00 | $42.09 | $10,372.70 |
| 10 | $10,372.70 | $0.00 | $0.00 | $42.26 | $10,414.96 |
| 11 | $10,414.96 | $0.00 | $0.00 | $42.43 | $10,457.40 |
| 12 | $10,457.40 | $0.00 | $0.00 | $42.60 | $10,500.00 |
Early-withdrawal penalties, changing rates, bank-specific day counts and tax rules are not included. Verify the CD disclosure.
Calculation method
How CD growth is calculated
APY is converted to the monthly rate that produces the same annual yield. For a nominal rate, the selected compounding frequency is converted to a monthly equivalent. Each month the calculator adds interest and the entered cash flows.
Detailed guide
CD maturity value, APY and interest
A certificate of deposit earns interest for a stated term, usually with restrictions or penalties for early withdrawal. This calculator accepts APY or a nominal annual rate and estimates maturity value, gross interest, optional tax and monthly cash flows.
APY already represents the compounded one-year yield. A nominal rate requires a compounding frequency, so the calculator converts that frequency to an equivalent monthly rate.
Calculate CD growth
2. Set the exact term
Use years or months and add recurring deposits or withdrawals only when the product permits them.
3. Choose interest treatment
Model interest added to principal or paid out separately, and optionally estimate tax on gross interest.
APY and nominal-rate conversion
Monthly rate from APY = (1 + APY)^(1/12) − 1
For a nominal rate compounded m times per year, the monthly equivalent is (1 + nominal rate ÷ m)^(m/12) − 1.
Interest is calculated on the opening monthly balance. The modeled monthly contribution or withdrawal occurs afterward.
CD example
A $10,000 CD at 5% APY for one year grows by applying the monthly rate equivalent to 5% annual yield. Monthly deposits increase the contribution total, while optional tax reduces net interest at maturity.
Check the product disclosure
Early-withdrawal penalty
This calculator does not subtract a penalty. CDs can forfeit part of earned interest or principal when closed early.
APY versus interest rate
APY includes compounding. Do not select APY and then apply a separate compounding boost to the same quoted yield.
Renewal and rate changes
The model assumes one constant term and rate. Automatic renewal can start a new CD at a different rate.
CD calculator questions
What is the difference between APY and APR?
APY includes compounding over a year. A nominal annual rate does not until a compounding frequency is applied.
Can a CD accept monthly deposits?
Many traditional CDs do not. Use zero monthly deposits unless the specific add-on CD permits them.
Does the calculator include early-withdrawal penalties?
No. Review the bank disclosure and subtract the stated penalty separately.
Is CD interest taxable?
Tax treatment depends on account and jurisdiction. The optional tax rate is only a simplified estimate.
Data sources
Updated: July 28, 2026