CD Calculator
See how much a certificate of deposit (CD) will earn. Enter your deposit, rate and term to get your balance at maturity, the interest earned, your interest after taxes and the maturity date. Works with an APY or an interest rate, for any term from a 3-month CD to a 12-month CD or 5-year CD.
Estimate only. Assumes the rate stays fixed for the whole term, interest stays in the CD and no early withdrawals. Taxes shown are a rough estimate.
Month by month
Interest earned and CD balance at the end of each month.
| Month | Interest | Total interest | Balance |
|---|
What a $10,000 CD earns by term
Here is $10,000 at 4.00% APY for common CD terms. Real rates differ by term, so check the APY each bank offers for the term you want.
| Term | Balance at maturity | Interest earned |
|---|---|---|
| 3 months | $10,098.53 | $98.53 |
| 6 months | $10,198.04 | $198.04 |
| 1 year | $10,400.00 | $400.00 |
| 18 months | $10,605.96 | $605.96 |
| 2 years | $10,816.00 | $816.00 |
| 3 years | $11,248.64 | $1,248.64 |
| 5 years | $12,166.53 | $2,166.53 |
The rate you choose matters as much as the term. The national average for a 12-month CD was 1.73% in September 2026, while the best 1-year CDs listed by NerdWallet paid up to 4.40% APY. On $10,000 for a year, that is $173 of interest versus $440.
12-month CD calculator: what a 1-year CD earns
A 12-month CD is the most popular term. Because APY already includes compounding, one year of interest is simply the deposit times the APY. Here is what common deposits earn in 12 months:
| Deposit | 1.73% APY (average) | 3.00% APY | 4.00% APY | 4.40% APY (top rates) |
|---|---|---|---|---|
| $5,000 | $86.50 | $150.00 | $200.00 | $220.00 |
| $10,000 | $173.00 | $300.00 | $400.00 | $440.00 |
| $25,000 | $432.50 | $750.00 | $1,000.00 | $1,100.00 |
| $50,000 | $865.00 | $1,500.00 | $2,000.00 | $2,200.00 |
The 1.73% column is the FDIC national average for 12-month CDs in September 2026, and 4.40% reflects the best 1-year rates listed in late September. On $10,000, picking a top rate instead of the average earns $267 more in a year. Treasury bills are another 1-year option with interest free from state tax; compare them in our Treasury bill calculator.
APY vs. interest rate
Banks show two numbers for a CD. The interest rate (sometimes called APR) is the base rate before compounding. The APY (annual percentage yield) includes compounding, so it shows what you actually earn in a year.
A 3.92% rate compounded daily is about 4.00% APY. Always compare CDs by APY, since banks can compound on different schedules. Choose Rate in the calculator if you only know the interest rate.
Worked example: $10,000 in a 1-year CD
You put $10,000 into a 12-month CD paying 4.00% APY. Your combined federal and state tax rate on interest is 22%.
- Balance at maturity: $10,000 × 1.04$10,400.00
- Interest earned$400.00
- Estimated tax on interest: $400 × 22%$88.00
- Interest after taxes$312.00
The same deposit at the 1.73% national average would earn $173 before taxes. Shopping around for a better rate is often worth more than choosing a longer term. If you plan to add money each month, use our savings goal calculator or compound interest calculator instead, since most CDs do not accept extra deposits.
What is a CD ladder?
A CD ladder splits your money across several CDs that mature at different times. For example, $10,000 could be split into five $2,000 CDs maturing in 1, 2, 3, 4 and 5 years. Each year one CD matures, so you get regular access to part of your money and can reinvest it at the current rate.
- More flexibility. Part of your money becomes available every year without an early withdrawal penalty.
- Less rate risk. You are not locked into one rate for your whole balance.
- Not for emergencies. Keep your emergency fund in a high-yield savings account you can reach any day.
Before you open a CD
- Check the early withdrawal penalty. It is often several months of interest and can be larger on longer terms.
- Confirm deposit insurance. CDs at FDIC-insured banks and NCUA-insured credit unions are protected up to $250,000 per depositor, per institution, for each ownership category.
- Know what happens at maturity. Many CDs renew automatically at the bank’s current rate unless you act during a short grace period.
- Remember taxes. Interest is usually taxable each year, even before the CD matures.
- Compare with Treasuries. Treasury bills and I bonds are free from state income tax, so they can beat a CD with a slightly higher rate. Check with our Treasury bill calculator and I bond calculator.
Frequently asked questions
How much does a 12-month CD earn?
A 12-month CD earns the deposit times the APY. At 4.00% APY, $10,000 earns $400 in one year; at the 1.73% national average it earns $173, and at a top rate of about 4.40% it earns $440. Interest is usually taxable in the year it is credited.
How much interest will I earn on a $10,000 CD?
It depends on the APY and the term. At 4.00% APY, a $10,000 CD earns $400 in one year. At the 1.73% national average for 12-month CDs, it earns $173. Over five years at 4.00% APY, the same $10,000 grows to about $12,166.53.
How is CD interest calculated?
CD interest compounds, usually daily or monthly. When a rate is quoted as APY, the balance at maturity is the deposit × (1 + APY) raised to the number of years. For a 12-month CD at 4.00% APY, $10,000 × 1.04 = $10,400.
What is the difference between APY and interest rate on a CD?
The interest rate (APR) does not include compounding, while APY does. A 3.92% rate compounded daily works out to about 4.00% APY. Use APY to compare CDs, because it shows what you actually earn in a year.
Is CD interest taxable?
Yes. CD interest is generally taxed as ordinary income in the year it is credited to your account, even if the CD has not matured. Your bank reports it on Form 1099-INT. CDs held in an IRA follow the IRA's tax rules instead.
What happens if I withdraw money from a CD early?
Most banks charge an early withdrawal penalty, often a set number of days or months of interest, and the penalty can be larger for longer terms. On a short CD it can wipe out most of the interest earned. Check the penalty before you open the CD.
This calculator is for educational purposes only and is not financial or tax advice. CD rates, compounding and penalties vary by bank. National average rate: FDIC, via FRED (September 2026). Top 1-year CD rate: NerdWallet, September 28, 2026.