π¦ CD Calculator
Certificate of deposit growth, APY math, and early withdrawal penalties.
CD Value at Maturity
Estimates for planning only, not financial advice.
What Is a CD, and What Will It Earn?
A certificate of deposit is a bank time deposit: you lock up a lump sum for a fixed term, usually 3 months to 5 years, and the bank pays you a guaranteed APY in return. The deal is simple. A $10,000 one-year CD at 4.5 percent APY becomes $10,450 at maturity, with zero market risk. In exchange for that guarantee, your money is stuck: cash out early and you pay a penalty of several months of interest. The calculator above projects the maturity value for any deposit, term, and rate, and prices the early withdrawal penalty so you can see exactly what breaking the deal costs.
How to Use This Calculator
Enter your deposit and term, then enter the rate either as APY (how CDs are advertised) or as a nominal APR with a compounding frequency (how the fine print sometimes quotes it). The calculator shows the maturity value, total interest, and the true APY either way. Tick the early withdrawal box to see what breaking the CD early costs after the penalty.
Enter your Deposit and the Term in years. CD terms typically run from 3 months (0.25 years) to 5 years.
Choose your Rate Entry. Pick APY and enter the advertised yield, or pick Nominal APR and enter the rate plus how often it compounds. The calculator converts APR to APY for you.
Optionally tick "Model an early withdrawal" and enter when you would cash out and the penalty in months of interest. The result shows the penalty in dollars and what you walk away with.
Compare the maturity value against keeping the money in savings. A CD wins only if its APY beats your savings APY by enough to justify locking the money up.
APY vs APR: The Formula
In the APY formula, r is the nominal APR as a decimal and n is the number of compounding periods per year. A 4.889 percent APR compounded monthly gives APY = (1 + 0.04889/12)^12 - 1 = 5.00 percent. That is why the advertised APY is the only number that matters for your final balance: two CDs with the same APY pay identically no matter how often they compound. The maturity value then grows geometrically: each year multiplies the balance by (1 + APY), so a 5-year CD at 5 percent APY turns $10,000 into $10,000 x 1.05^5 = $12,762.82.
For terms under a year, the math is proportional: a 6-month CD at 4 percent APY earns roughly 2 percent, though the exact figure depends on the bank's day-count method. The calculator handles fractional years the same way, converting the APY to an exact monthly rate and compounding for the right number of months.
Worked Example
Deposit $10,000 in a 5-year CD at 5 percent APY. Maturity value = $10,000 x (1.05)^5 = $12,762.82, which is $2,762.82 of interest. Now suppose you break the CD after 12 months and the penalty is 6 months of interest. After 12 months the balance is $10,500.00. The monthly rate is (1.05)^(1/12) - 1 = 0.4074 percent, so 6 months of interest on the deposit is about $244.45. You walk away with $10,500.00 - $244.45 = $10,255.55, keeping only about half the interest you earned. The penalty math is why breaking a CD early is rarely worth it unless rates have jumped dramatically.
What $10,000 Earns at 4.5 Percent APY
| Term | Balance at maturity | Interest earned |
|---|---|---|
| 1 year | $10,450.00 | $450.00 |
| 3 years | $11,411.66 | $1,411.66 |
| 5 years | $12,461.82 | $2,461.82 |
The extra two years from year 3 to year 5 earn $1,050.16, more than the entire first year, because the interest itself starts earning interest. That is compounding doing its quiet work inside a product most people think of as boring. Boring is the point: the rate is locked, the number is certain, and you can plan around it.
CD vs High-Yield Savings Account
A CD and a high-yield savings account are cousins, and the choice comes down to one question: might you need the money before the term ends? A CD pays a higher rate because you commit; a savings account pays a little less because you can withdraw anytime. If the CD pays 4.5 percent and your savings account pays 4.2 percent, the CD earns $30 more per year on $10,000, which is a thin reward for locking your money up. My take: only take the CD when the rate gap is meaningful, at least half a point, and you are confident about the timeline. Otherwise the flexibility of the savings account is worth more than the extra dollars.
There is one more angle. Savings account rates float with the market, while a CD locks yours in. If you believe rates are about to fall, locking a CD today protects your yield. If you believe rates will rise, staying liquid in savings lets you capture the increase. You cannot know for sure, which is exactly why laddering exists: it spreads your bets across time instead of forcing one prediction.
Choosing a CD Term
Match the term to when you need the money, not to the highest rate. A 5-year CD at 5 percent beats a 1-year CD at 5.25 percent if you will just roll the 1-year CD into unknown future rates. When the yield curve is inverted and short terms pay more, laddering captures the high short rates while keeping money freeing up regularly. Also check the minimum deposit and whether the CD is callable: a callable CD lets the bank redeem it early if rates fall, which transfers the interest-rate risk back to you. No-penalty CDs exist too, offering CD-like rates with savings-like flexibility after a short initial lock.
Related Tools
Compare your options: our savings calculator projects the flexible alternative, the APR calculator decodes rate quotes, and the inflation calculator shows whether your CD rate actually grows your purchasing power.
Estimates for planning only, not financial advice.
Frequently Asked Questions
What is a CD and how does it work?
A certificate of deposit is a bank time deposit: you lock up a lump sum for a fixed term, from 3 months to 5 years, and the bank pays a fixed APY in return. Rates are usually higher than savings accounts because your money is committed. At maturity you can withdraw, renew, or roll the balance into a new CD. US bank CDs are FDIC insured up to $250,000 per depositor per bank.
What is the difference between APY and APR on a CD?
APR is the nominal yearly rate before compounding, while APY reflects the rate after compounding is counted: APY = (1 + r/n)^n - 1, where r is the APR and n is the number of compounding periods per year. A 4.90 percent APR compounded daily equals about 5.02 percent APY. CDs are always advertised by APY, so that is the number that determines your final balance.
What happens if I withdraw a CD early?
You pay an early withdrawal penalty, typically 3 to 12 months of interest depending on the CD term. On a 5-year CD the penalty is often 12 months of interest; on a 1-year CD it is often 3 months. The penalty is usually taken from accrued interest, but on some CDs it can eat into your principal. Use the early withdrawal section below to price your specific penalty.
Are CD rates fixed for the whole term?
Traditional CDs have a fixed rate locked at purchase, so your maturity value is guaranteed regardless of what the Fed does. The trade-off is opportunity risk: if rates rise after you buy, your money is stuck earning the old rate unless you pay the penalty to break the CD. Bump-up and step-up CDs allow limited rate increases, usually at a slightly lower starting rate.
What is a CD ladder and should I build one?
A CD ladder splits your money across CDs with staggered maturities, for example one-fifth each in 1, 2, 3, 4, and 5-year CDs. As each rung matures you reinvest at the new 5-year rate. You get the higher long-term rates on average while a chunk of money frees up every year. It is the standard strategy for money you will not need all at once.
Are CD earnings taxed?
Yes. CD interest is taxed as ordinary income in the year it is credited, even if you do not withdraw it until maturity. Your bank sends a 1099-INT for interest over $10. Holding CDs inside an IRA avoids the yearly tax bite, but then early withdrawal rules of the IRA also apply. This calculator shows pre-tax values.
How much does a $10,000 CD make in a year?
It depends on the APY. At 4.5 percent APY, a $10,000 one-year CD earns $450 in interest, for a $10,450 balance at maturity. The quick math for a one-year CD is simple: multiply the deposit by the APY. For longer terms or different compounding, enter your exact numbers in the calculator above.
Can I earn 7% APY on a CD?
Not usually. Competitive CD rates in the US have recently run between 4 and 5 percent APY, depending on the bank and term. A 7 percent CD would need the Federal Reserve to hold its benchmark rate above that level, which is rare. If you see 7 percent advertised, read the fine print: it may be a short promotional teaser rate or a specialty product with strings attached.
What is the minimum deposit to open a CD?
It varies by bank. Many online banks let you open a CD with $0 to $500, while traditional banks often set $500 to $1,000 minimums, and premium or jumbo CDs can require $10,000 to $100,000. Promotional rates sometimes carry higher minimums. Shop around: the best rate with a minimum you can meet beats a slightly better rate you cannot reach.
What affects CD rates?
Three forces set CD rates. First, the Federal Reserve's benchmark rate: when it rises, CD rates follow, and when it falls, they drop. Second, each bank's need for deposits: online banks hungry for funding often pay more than big banks sitting on cash. Third, the term: longer terms usually pay more, except when the market expects rates to fall. Watch Fed moves and compare online banks against your own.
CD vs savings account: which is better?
Pick the CD when the rate gap is meaningful and your timeline is certain. A CD pays more because you commit your money; a high-yield savings account pays a little less but lets you withdraw anytime. If the CD pays only 0.2 points more, the flexibility of savings is worth more than the extra dollars. If rates are about to fall, locking a CD protects your yield; if they might rise, staying liquid wins.
Do CDs offer guaranteed returns?
Yes, as long as you hold to maturity. The rate is locked at purchase, so your maturity value is contractually guaranteed no matter what happens to market rates. Your principal is also safe: FDIC insurance covers up to $250,000 per depositor per bank. The one way to lose is breaking the CD early, where the penalty can eat into interest and sometimes principal.