№ 053 · Savings cluster
CD Calculator
Lock a lump sum at a fixed APY for a fixed term and the return is guaranteed — no market risk, FDIC insured. Enter your deposit, the rate the bank quotes, and the term to see exactly what it’s worth at maturity, how much of that is interest, and what breaking it early would cost.
Fixed APY · guaranteed at maturity
Saving a bit every month instead of locking a lump sum? Project that with the Compound Interest Calculator, or work backward from a target with the Savings Goal Calculator. Comparing against tradeable fixed income? See the Bond Yield Calculator, or convert a quoted rate to its true yield with the APR vs APY Calculator.
Your deposit01
$
The rate02
%
The term03
Early-withdrawal penalty04
Months of interest a bank forfeits if you break the CD before maturity.
Matures in 2 yr
$11,025.00
from $10,000.00 at 5.00% APY
$1,025.00 guaranteed interest$10,775.00 if broken early
Maturity value$11,025.00
Interest earned$1,025.00
APY5.00%
Early-withdrawal penalty$250.00
- Balance$11,025.00
- Contributed$10,000.00
| Month 0 | balance $10,000.00, contributed $10,000.00 |
|---|---|
| Month 1 | balance $10,040.74, contributed $10,000.00 |
| Month 2 | balance $10,081.65, contributed $10,000.00 |
| Month 3 | balance $10,122.72, contributed $10,000.00 |
| Month 4 | balance $10,163.96, contributed $10,000.00 |
| Month 5 | balance $10,205.37, contributed $10,000.00 |
| Month 6 | balance $10,246.95, contributed $10,000.00 |
| Month 7 | balance $10,288.70, contributed $10,000.00 |
| Month 8 | balance $10,330.62, contributed $10,000.00 |
| Month 9 | balance $10,372.70, contributed $10,000.00 |
| Month 10 | balance $10,414.96, contributed $10,000.00 |
| Month 11 | balance $10,457.40, contributed $10,000.00 |
| Month 12 | balance $10,500.00, contributed $10,000.00 |
| Month 13 | balance $10,542.78, contributed $10,000.00 |
| Month 14 | balance $10,585.73, contributed $10,000.00 |
| Month 15 | balance $10,628.86, contributed $10,000.00 |
| Month 16 | balance $10,672.16, contributed $10,000.00 |
| Month 17 | balance $10,715.64, contributed $10,000.00 |
| Month 18 | balance $10,759.30, contributed $10,000.00 |
| Month 19 | balance $10,803.13, contributed $10,000.00 |
| Month 20 | balance $10,847.15, contributed $10,000.00 |
| Month 21 | balance $10,891.34, contributed $10,000.00 |
| Month 22 | balance $10,935.71, contributed $10,000.00 |
| Month 23 | balance $10,980.27, contributed $10,000.00 |
| Month 24 | balance $11,025.00, contributed $10,000.00 |
How the balance builds
| When | Interest | Balance |
|---|---|---|
| Year 1 | $500.00 | $10,500.00 |
| Year 2 | $1,025.00 | $11,025.00 |
How it works · methodology
The math, in the open.
maturity = principal × (1 + APY)^(termMonths / 12) interest = maturity − principal penalty = principal × APY × (penaltyMonths / 12)
- principal
- The lump sum you deposit
- APY
- Annual percentage yield (as a decimal)
- termMonths
- Length of the CD in months
- penaltyMonths
- Months of interest forfeited if broken early
Assumptions & limits
- The rate is fixed for the whole term and the deposit is held to maturity — that is the deal a CD offers.
- APY already accounts for compounding, so no compounding-frequency input is needed; enter the rate exactly as the bank advertises it.
- The early-withdrawal figure is a worst-case illustration — the real penalty depends on when you withdraw and your bank’s specific terms.
- Growth is shown before tax. CD interest is taxable as ordinary income in the year it is credited.
Sources
By the MintNumber Editorial Team·Reviewed
Frequently asked
Questions about CDs
What is a certificate of deposit?
A certificate of deposit, or CD, is a savings product where you lock a lump sum with a bank for a fixed term — six months, a year, five years — in exchange for a fixed, guaranteed interest rate. You cannot add to it or, ordinarily, take money out before the term ends without paying a penalty. In return for giving up that flexibility you typically earn more than an ordinary savings account, and at an FDIC-insured bank the deposit is protected up to the federal limit.
What is the difference between APY and APR?
APY — annual percentage yield — is the rate that already accounts for compounding within the year, so it tells you the true amount you will actually earn. APR is a simple annual rate that ignores compounding. Banks advertise CDs and savings accounts in APY because it is the honest, all-in figure, which is why this calculator takes an APY: enter the number the bank quotes and the maturity value is exact, no compounding-frequency guesswork required.
How does a CD differ from a high-yield savings account?
Both pay interest on cash, but a savings account has a variable rate the bank can change at any time and lets you withdraw whenever you like. A CD locks the rate for the whole term — a real advantage when rates are falling, a drawback when they are rising — and charges a penalty if you break it early. Use a CD for money you know you will not need until a specific date; use a savings account for money that has to stay reachable.
What is the early-withdrawal penalty?
If you cash out a CD before it matures, the bank claws back some of the interest — commonly three to twelve months of it, depending on the term. This calculator illustrates the worst case by forfeiting that many months of interest from the maturity value, but the real penalty depends on when you withdraw and the exact terms in your account agreement. Read those terms before you commit money you might need early.
Is the interest on a CD taxable?
Yes. Interest a CD earns is taxable as ordinary income in the year it is credited, even on a multi-year CD where you have not yet touched the money, and the bank reports it on a 1099-INT. This calculator shows pre-tax growth, so your after-tax return will be lower. A CD held inside a tax-advantaged account such as an IRA is treated differently.
How is this different from the compound interest calculator?
A CD is a single locked deposit at a fixed, guaranteed rate, so this calculator takes one APY and one term and shows the exact maturity value. The compound interest calculator is built for an investment you keep adding to — an initial amount plus ongoing monthly contributions at an assumed, not guaranteed, market return. Use this for a CD or a one-time deposit; use compound interest when you are contributing every month.