CD Calculator
Work out what a certificate of deposit is worth at maturity. Enter the deposit, term and rate as APY or APR, pick the compounding frequency and see the interest, the schedule and what an early withdrawal would cost.
The penalty is estimated as N months of simple interest on the deposit at the APR. Banks differ, so check your CD agreement.
Balance growth
| Month | Interest | Total interest | Balance |
|---|
Estimates only, not financial advice. Real CD earnings depend on the bank's day-count method, rounding and whether interest is paid out or compounded.
How to use the CD Calculator
- Enter the deposit you plan to put in the CD and choose your currency.
- Set the term in months, years or days.
- Type the rate the bank quotes and choose whether it is the APY or the APR, then pick the compounding frequency.
- Optionally add the penalty in months of interest and the month you might withdraw early.
- Press Calculate to read the maturity value, interest, equivalent rate, schedule and chart. Use Copy summary or Export CSV to keep the numbers.
CD formulas: maturity value, APY and APR
A CD grows by compound interest. With a deposit P, nominal rate APR, n compounding periods per year and a term of t years:
- Maturity value = P × (1 + APR / n)n × t = P × (1 + APY)t
- APY = (1 + APR / n)n − 1
- APR = n × ((1 + APY)1/n − 1)
- Early-withdrawal penalty ≈ P × APR ÷ 12 × months of interest
Example: $10,000 in a 12-month CD at 4.50% APY compounded monthly. The APR is 12 × (1.0451/12 − 1) = 4.410%, the value at maturity is $10,450.00 and the interest is $450.00. A 3-month penalty is 10,000 × 0.0441 ÷ 12 × 3 ≈ $110.24, so cashing out after 6 months pays about $10,112.28.
Interest on a $10,000 CD by term and rate
| APY | 6 months | 1 year | 2 years | 3 years | 5 years |
|---|---|---|---|---|---|
| 3.00% | $148.89 | $300.00 | $609.00 | $927.27 | $1,592.74 |
| 4.00% | $198.04 | $400.00 | $816.00 | $1,248.64 | $2,166.53 |
| 4.50% | $222.52 | $450.00 | $920.25 | $1,411.66 | $2,461.82 |
| 5.00% | $246.95 | $500.00 | $1,025.00 | $1,576.25 | $2,762.82 |
Common early-withdrawal penalties
| CD term | Typical penalty |
|---|---|
| Under 12 months | About 3 months of interest |
| 12 to 24 months | About 6 months of interest |
| 2 to 5 years | About 6 to 12 months of interest |
| Over 5 years | About 12 to 24 months of interest |
Penalties vary a lot between banks and credit unions, and some offer no-penalty CDs at a lower rate. Always read the account disclosure before you open a CD. A CD ladder, which splits your money across several maturities, keeps some cash available without paying penalties.
Frequently asked questions
How is CD interest calculated?
Banks compound the nominal rate (APR) a set number of times per year. The value at maturity is deposit × (1 + APR / n)^(n × years), which is the same as deposit × (1 + APY)^years. The calculator uses the APY form, so the compounding frequency only matters for converting between APR and APY.
What is the difference between APY and APR on a CD?
APR is the stated yearly rate before compounding. APY (annual percentage yield) includes the effect of compounding, so it is the rate you really earn in a year. Banks usually advertise CDs by APY, which makes offers easier to compare.
How much is a CD early-withdrawal penalty?
Most banks charge a number of months of interest, for example 3 months on a 1-year CD and 6 to 12 months on longer terms. This tool estimates it as deposit × APR ÷ 12 × months. If you withdraw very early, the penalty can be larger than the interest earned and cut into your deposit.
Does the compounding frequency change my result?
If you enter the APY, the maturity value is the same whatever the compounding, because the APY already includes it. If you enter the APR, more frequent compounding gives a slightly higher APY and a higher maturity value.
Is CD interest taxable?
In the US, CD interest is usually taxed as ordinary income in the year it is credited, even if you do not withdraw it. The calculator shows pre-tax amounts. This is an estimate only, not tax or financial advice.
Is my data saved or sent anywhere?
No. All calculations run in your browser and nothing you type is uploaded. Only your currency and compounding choice are remembered on this device.