See what a CD pays by the end of its term. Enter the APY or the interest rate and compounding, and check what you'd lose by cashing it in early.
Estimates for planning, not financial, tax or legal advice. Figures use US rules unless the page says otherwise.
How CD interest is calculated
If the bank gives you the APY, that already includes compounding, so the value at maturity is:
Value = deposit × (1 + APY)months ÷ 12
If it gives the interest rate (APR) and how often it compounds (n times a year):
Value = deposit × (1 + rate ÷ n)n × months ÷ 12 APY = (1 + rate ÷ n)ⁿ − 1
Worked example
$10,000 in a 12-month CD at 5% APY is worth $10,500.00 at maturity. At a 5% rate compounded daily it's worth $10,512.67, an APY of 5.127%. An 18-month CD at 4.5% APY: 10,000 × 1.0451.5 = $10,682.54.
Early withdrawal penalties
Most CDs charge a penalty of a set number of months' interest, often 3 months on short CDs and 6 to 12 months on longer ones. Calcist works it out as simple interest on the deposit: deposit × rate × months ÷ 12. If you cash in a 5% APY CD after 6 months with a 3-month penalty, you'd have $10,246.95 minus $125.00 = $10,121.95. Cash it in very early and the penalty can eat into your deposit. Banks must tell you how they calculate the penalty before you open the CD, so check your disclosure.
Limitations
- Banks count actual days and credit interest on set dates, so their figure can differ by a few cents.
- Some CDs pay interest out instead of compounding it. Then the value at maturity is closer to simple interest.
- CD interest is taxable each year as it's credited, even before the CD matures.
Sources
How we checked this
Before every update, this calculator is run in a real browser with these known answers, and it must match all of them:
- $10,000 at 5% APY for 12 months = $10,500 ✓
- 5% APR compounded daily for 12 months = $10,512.67 ✓
- 4.5% APY for 18 months = $10,682.54 ✓
- Cashed at 6 months with 3 months' interest penalty: $10,121.95 ✓
- Cashed at 1 month with 6 months' penalty: $9,790.74, less than deposited ✓
Last checked October 26, 2026. Spotted something wrong? The math is done in your browser with the formula shown on this page, so you can check any result by hand.
Questions people ask
How much does a $10,000 CD earn in a year?
At 5% APY, exactly $500. At 4% APY, $400. APY is the yearly earnings on the deposit, so multiply.
What is the difference between APY and APR on a CD?
The rate (APR) doesn't include compounding; the APY does. Daily compounding at 5% gives an APY of 5.127%. Compare CDs by APY.
How is the CD early withdrawal penalty calculated?
Usually as a number of months (or days) of simple interest on the amount withdrawn, at the CD's rate. 3 months' interest on $10,000 at 5% is $125.
Can I lose money on a CD?
Not at maturity on an FDIC- or NCUA-insured CD within the limits. But an early withdrawal penalty can be larger than the interest earned so far, so you can get back less than you deposited.
Is a CD better than a high-yield savings account?
A CD locks in a rate for the term; a savings rate can change any time but you can withdraw freely. Compare with the savings calculator.