--- title: "CD Calculator" date: 2026-10-01 author: "Steven Burnett" featured_image: "https://coinlaw.io/wp-content/uploads/2026/10/cd-calculator.jpg" --- # CD Calculator The free CD calculator shows what a certificate of deposit pays: the balance at maturity, the interest earned, the annual percentage yield (APY) and the average interest per month. Enter the rate as an APY or an annual percentage rate (APR) and the term in months to compare CDs. A $10,000 CD at 4.5% APY for 12 months pays **$450.00**. CD Calculator Examples Reset $10k, 4.5% APY, 12 months $25k, 5% APY, 6 months $50k, 4% APY, 5 years Deposit $ Rate % Term months Rate is quoted as APYAPY (already includes compounding) APRAPR (nominal, compounds below) Compounding (APR only) DailyDaily (365) MonthlyMonthly (12) QuarterlyQuarterly (4) AnnualAnnual (1) Balance at maturity $10,450.00 Copy A $10,000 CD at 4.5% APY for 12 months pays $450.00 in interest, $10,450.00 at maturity. Informational only, not financial advice. Balance at maturity$10,450.00 Interest earned$450.00 APY4.500% Average interest per month$37.50 Copy all details Save scenario Share result Download CSV Saved scenarios Saved in this browser only. Each column is recalculated whenever the page loads. Balance over the term Interest adds $450.00 over 12 months. Growth schedule | Period | Interest so far | Balance | |---|---|---| How this is calculated How it worksBalance = deposit × (1 + APY)^(months ÷ 12), with APY as defined in [Regulation DD, Appendix A (opens in new window)](https://www.ecfr.gov/current/title-12/chapter-X/part-1030/appendix-Appendix%20A%20to%20Part%201030). A quoted APR is first converted to APY at the chosen compounding. Early-withdrawal penalties and taxes are not included. Not coveredNo early-withdrawal penalty or taxes; the quoted rate holds to maturity. Privacy**Your numbers never reach our server.** The math runs on your device, inside this page. CorrectionsReport an error in the math to [media@coinlaw.io](mailto:media@coinlaw.io?subject=Correction%3A%20CD%20Calculator); every report is reviewed and confirmed errors are corrected. Include the inputs and the answer you expected. With your permission, we thank you by name on this page. FeedbackHow useful was this tool? The figures shown are the worked example. Enable JavaScript to calculate with your own numbers. ## How to Use the CD Calculator Three numbers drive this certificate of deposit calculator: a deposit, a rate quoted as an APY or APR, and a term in months. It runs in your browser, so nothing you type reaches our server. 1. Type the initial deposit, the amount going into the CD, in “Deposit”. The Federal Deposit Insurance Corporation (FDIC) and National Credit Union Administration (NCUA) limits below count it plus accrued interest or posted dividends. 2. Enter the rate the bank quotes in “Rate”. 3. Set “Term” in months, from 1 to **120**. A 6-month CD is 6 and a 5-year CD is **60**. 4. Pick “APY (already includes compounding)” or “APR (nominal, compounds below)” in “Rate is quoted as”. According to [Regulation DD](https://www.ecfr.gov/current/title-12/chapter-X/part-1030/section-1030.8), the federal Truth in Savings rule, an ad that states a rate of return must state the rate as an annual percentage yield, so a bank’s CD ad that quotes a rate shows an APY. 5. For an APR, choose “Compounding (APR only)”: Daily (365), Monthly (12), Quarterly (4) or Annual (1). “Balance at maturity” leads the results, then “Interest earned”, “APY” and “Average interest per month”. A chart and a “Growth schedule” table follow, monthly up to 24 months and yearly beyond. According to the [CFPB’s CD explainer](https://www.consumerfinance.gov/ask-cfpb/what-is-a-certificate-of-deposit-cd-en-917/), shoppers should compare different offers by looking at the term, the interest rate you earn, and the amount of the penalty for withdrawing money before the end of the term. ## How CD Interest Is Calculated Each result starts from the APY, applied for the share of a year the term covers, so a 12-month term applies the full APY once. Three formulas produce every figure in the panel: - Balance at maturity = deposit × (1 + APY)^(months ÷ 12). - An APR is converted first: APY = (1 + APR ÷ n)^n – 1, where n is the number of compounding periods a year. - Average interest per month = interest earned ÷ months. Per Regulation DD, the general formula in [Appendix A of the rule](https://www.ecfr.gov/current/title-12/chapter-X/part-1030/appendix-Appendix%20A%20to%20Part%201030) is APY = 100 \[(1 + Interest/Principal)^(365/Days in term) – 1\]. Solved for interest, it is the calculator’s formula, with months ÷ 12 for days ÷ 365. The rule’s worked example tests it. Regulation DD says that if an institution pays $30.37 in interest on a $1,000 six-month certificate of deposit (where the six-month period used by the institution contains 182 days), then “using the general formula above, the annual percentage yield is 6.18%.” Enter a “Deposit” of 1,000, a “Rate” of 6.18 as an APY and a “Term” of 6, and the calculator returns **$30.44**. Day counts explain the gap. Six months is half a year in the calculator, but that bank’s period held 182 days. With 182 days, the same formula gives $30.35, two cents under the rule’s figure because 6.18% is rounded. For CDs offered in multiples of months, Regulation DD lets institutions base the number of days on either the actual number of days during the applicable period, or the number of days that would occur for any actual sequence of that many calendar months; the calculator’s half-year approximates both. An APR changes the math. The FDIC’s [Money Smart guide](https://catalog.fdic.gov/catalog/sfc/servlet.shepherd/document/download/069t000000BcgrhAAB) says APY “is expressed as a percentage and includes the effects of compounding.” Compounding frequency therefore matters only for an APR. On $10,000 over 12 months, 4.5% entered as an APY pays **$450.00** under any schedule; entered as an APR compounded daily, it pays **$460.25**. ### How Do I Calculate How Much Money My CD Will Make? Multiply the deposit by 1 plus the APY raised to the power of months ÷ 12, then subtract the deposit; an APR needs converting to an APY beforehand. For the example’s 12 months at 4.5% APY on $10,000, that is **$450.00**. ## CD Calculator Example: $10,000 at 4.5% APY for 12 Months Opening the calculator loads the one-year Examples preset: a “Deposit” of 10,000, a “Rate” of 4.5 quoted as an APY and a “Term” of 12. The steps below reproduce its panel line by line. 1. APY: the rate is already an APY, so “APY” reads 4.500%. 2. Balance at maturity: 12 months is one full year, so the deposit grows by 1.045 once, to **$10,450.00**. 3. Interest earned: the balance minus the deposit leaves **$450.00**. 4. Average interest per month: dividing $450.00 by 12 gives **$37.50**. 5. Monthly schedule: each month multiplies the balance by 1.045 to the power of 1/12, so month 1 adds **$36.75** and month 12 adds **$38.26**. ### How Much Will $10,000 Make in a 6-Month CD? At 4.5% APY, a six-month CD on $10,000 earns **$222.52**, a little under half the 12-month $450.00, because the later months earn interest on the earlier ones. The [FDIC’s national rate](https://www.fdic.gov/national-rates-and-rate-caps) for a 6-month CD was 1.41% as of September 21, 2026. ## What Your CD Result Means “Balance at maturity” is what the CD pays if the rate holds for the whole term and every dollar of interest stays in the account, with no withdrawals, penalties or taxes along the way. Regulation DD’s general calculation assumes all principal and interest remain on deposit for the entire term and that no other transactions (deposits or withdrawals) occur during the term, an assumption that shall not be used if an institution requires, as a condition of the account, that consumers withdraw interest during the term. Interest paid out does not compound. The [SEC](https://www.investor.gov/additional-resources/general-resources/publications-research/info-sheets/high-yield-cds-protect-your) tells CD buyers to ask how often the bank pays interest (for example, monthly or semi-annually) and confirm how you’ll be paid. When interest leaves by check or transfer, the balance stays at the deposit, and “Balance at maturity” overstates what the CD will hold. ### Common Mistakes When Using a CD Calculator - Years typed into “Term”. On the **$50,000** five-year preset at 4% APY, entering 5 rather than 60 returns **$50,823.81**, not **$60,832.65**. - An APR typed as an APY, which skips the conversion and understates the interest unless the APR compounds annually. ## APY vs APR on a CD: Which Rate to Enter Enter the APY whenever the bank quotes one. Under the [Regulation DD advertising rule](https://www.ecfr.gov/current/title-12/chapter-X/part-1030/section-1030.8), the interest rate may be stated in conjunction with, but not more conspicuously than, the annual percentage yield, and [account disclosures](https://www.ecfr.gov/current/title-12/chapter-X/part-1030/section-1030.4) list the annual percentage yield and the interest rate together. Run both ways on the example’s deposit and term: | Rate entered as | Compounding | APY shown | Interest earned | |---|---|---|---| | APY | Not used | 4.500% | $450.00 | | APR | Daily (365) | 4.602% | $460.25 | | APR | Monthly (12) | 4.594% | $459.40 | | APR | Quarterly (4) | 4.577% | $457.65 | | APR | Annual (1) | 4.500% | $450.00 | *Sources: Regulation DD Appendix A (APY method), CD Calculator outputs* Money Smart adds that “The more often your money compounds, the more interest you earn”, and for an APR that holds: daily beats annual by **$10.25** here. Once the rate is an APY, compounding is already inside it and that gap disappears. On a quoted CD rate, the label decides whether the compounding schedule matters at all. ## How to Choose a CD Term Length Match the CD term to when the money will be needed, since leaving early usually means a penalty. The CFPB’s guidance is short: “Select your CD maturity date based on your expected needs.” A [separate CFPB answer](https://www.consumerfinance.gov/ask-cfpb/the-interest-rate-offered-for-cds-certificates-of-deposit-is-low-is-there-anything-i-can-do-about-that-en-921/) says that, generally, you may be able to get a higher interest rate by selecting a later maturity date. Under the FDIC rule behind its [monthly table](https://www.fdic.gov/national-rates-and-rate-caps), the national rate is the average of rates paid by all insured depository institutions and credit unions for which data is available, with rates weighted by each institution’s share of domestic deposits. Those rates as of September 21, 2026 were 1.73% at 12 months, 1.61% at 24 months and 1.38% at 60 months. Every longer term in the FDIC table averaged below 12 months, though 24 months still topped 6 months. At the example’s deposit and APY, interest grows with the term: - **3 months:** **$110.65**. - **6 months:** **$222.52**. - **18 months:** **$682.54**. - **24 months:** **$920.25**. ### Is a 4% CD Good Right Now? The FDIC’s 12-month CD national rate was 1.73% as of September 21, 2026, so a 12-month CD at 4% APY sat **2.27** percentage points above it. The SEC calls inflation risk the “principal concern for individuals investing in cash equivalents”, and comparing a CD’s APY with the [latest US inflation readings](/inflation-statistics/) shows how much of the interest is growth in spending power. CoinLaw does not rate offers. ### How to Model a CD Ladder A CD ladder splits one sum across several CDs that mature on different dates. Split $10,000 into four $2,500 CDs at 6, 12, 18 and 24 months; at 4.5% APY they earn: - **6 months:** **$55.63**. - **12 months:** **$112.50**. - **18 months:** **$170.63**. - **24 months:** **$230.06**. Real rungs usually carry different APYs. For a rung set to renew automatically, the [CFPB’s rollover guidance](https://www.consumerfinance.gov/ask-cfpb/what-is-a-certificate-of-deposit-cd-rollover-or-renewal-en-923/) says a bank or credit union is required to send you a notice in writing before the CD matures, and the notice will tell you when your current CD ends and whether it will renew automatically. ## CD Early Withdrawal Penalties A CD early withdrawal penalty is the cost of breaking the term; the calculator assumes you hold to maturity. The CFPB explainer says withdrawing money early means paying a penalty fee to the bank, and the SEC adds that you may have to pay an early withdrawal penalty or forfeit a portion of the interest you earned. - [Regulation D](https://www.ecfr.gov/current/title-12/chapter-II/subchapter-A/part-204/section-204.2) defines a time deposit as one that bars withdrawals within six days of deposit unless it carries an early withdrawal penalty of at least seven days’ simple interest on amounts withdrawn within the first six days after deposit. - Regulation DD requires the account disclosure to give a statement that a penalty will or may be imposed for early withdrawal, how it is calculated, and the conditions for its assessment. - For a brokered CD, one bought through a broker, the SEC warns that if you buy a brokered CD and need to get your money back early, you may lose some of your principal. For a penalty stated in months of interest, “Average interest per month” gives a rough size: about **$37.50** a month on the example. ## FDIC and NCUA Limits: Check the Balance at Maturity Deposit insurance counts a CD’s accrued interest along with the deposit. Per the [FDIC’s deposit insurance FAQ](https://www.fdic.gov/resources/deposit-insurance/faq), deposits are insured up to at least $250,000 per depositor, per FDIC-insured bank, per ownership category, counting principal plus any interest accrued or due to the depositor, through the date of default. An ownership category, the FDIC explains, generally means the manner in which you hold your funds. Its example: if a customer had a CD account in her name alone with a principal balance of $195,000 and $3,000 in accrued interest, the full $198,000 would be insured. [NCUA share insurance](https://ncua.gov/consumers/share-insurance-coverage) covers a time deposit such as a share certificate, including principal and any posted dividends through the date of the insured credit union’s closing, up to the insurance limit. The [credit union statistics](/credit-union-statistics/) include recent growth in share certificate balances. Check “Balance at maturity” against the limit. For a deposit equal to the standard amount, at the example’s APY and term: - **Balance at maturity:** **$261,250.00**. - **Above the standard amount:** **$11,250.00**, if the CD is the only deposit in that ownership category at that bank. - **Largest deposit that stays at the limit:** **$239,234.45**. A [count of US bank failures by year](/bank-failures-statistics/) shows how often insured banks have failed. ### Who Has a 9.5% APY CD? A 9.5% APY sits **3.36** percentage points above the FDIC’s 60-month rate cap of 6.14% as of September 21, 2026. The caps generally limit a less than well capitalized institution from soliciting deposits by offering rates that significantly exceed rates in its prevailing market (a bank below the top capital tier). FDIC [CD shopping tips](https://www.fdic.gov/consumer-resource-center/2023-11/shopping-certificate-deposit) warn that CDs or other products may be offered by a company that is not federally insured. The SEC adds that some long-term, high-yield CDs have call features, letting the bank end them early. ## Is there anything else my agent or I should know about this page? Yes. The calculator runs in the browser and nothing you enter reaches our server. It assumes the quoted rate holds to maturity and leaves out early-withdrawal penalties and taxes. A CD closed early or held in a taxable account ends with less than the figure shown. A quoted APR is converted to an APY at the compounding you pick before the balance is worked out; a quoted APY is used as it is. The formula is the Regulation DD definition of APY solved for interest. The worked example above uses the tool’s own pinned inputs, so the page and the tool agree to the cent. CoinLaw publishes this page for information and gives no financial advice; the bank’s own disclosure governs the terms of any CD. ## Conclusion A $10,000 CD at 4.5% APY for 12 months ends at **$10,450.00**, $450.00 of it interest, or $37.50 a month on average. In the CD calculator, savers can compare APY and APR quotes, model ladders and check “Balance at maturity” against the insurance limit. For money needed before maturity, the [emergency savings data](/emergency-fund-statistics/) track how many US adults could cover three months of expenses. ## More Finance Calculators [All finance calculators (3) →](https://coinlaw.io/finance-calculators/) - [ Final balance 10 years at 6% $50,969.84 Finance In your browser Compound Interest Calculator Growth with monthly deposits, or what a goal needs. $16,969.84Total interest earned → ](https://coinlaw.io/compound-interest-calculator/)