CD Calculator

A Certificate of Deposit (CD) is one of the safest ways to grow your savings. Use this free CD Calculator to determine exactly how much interest your investment will earn by the time it reaches maturity. Calculate your final balance, total interest earned, and your Annual Percentage Yield (APY).

How Does a CD Work?

A Certificate of Deposit is a fixed-term investment offered by banks and credit unions. You agree to leave a lump sum of money untouched in the account for a specific period of time (the "term"), and in exchange, the bank pays you a guaranteed, fixed interest rate. Because your money is locked in, CDs generally offer significantly higher interest rates than traditional savings accounts.

CD Compound Interest Formula

The interest earned on a CD is calculated using the standard compound interest formula. This means you don't just earn interest on your initial deposit, but you also earn interest on the interest that has already been added to your account.

• A = Final accumulated amount (End Balance)
• P = Principal (Initial Deposit)
• r = Annual interest rate (in decimal form)
• n = Number of times interest is compounded per year (e.g., 12 for monthly)
• t = Time the money is invested in years

CDs vs. Other Investments

Not sure if a CD is the right place for your cash? Here is how Certificates of Deposit compare to other common investment vehicles:

APR vs. APY: Understanding Your Return

When shopping for CD rates, you will see two different percentages: APR (Annual Percentage Rate) and APY (Annual Percentage Yield).

• APR: This is the flat, stated interest rate on the account without taking compounding into effect.
• APY: This is the true, effective rate of return you will earn over one year. It accounts for compounding interest (earning interest on your interest). The more frequently your CD compounds (e.g., daily vs. annually), the higher your APY will be compared to your APR.

Our calculator automatically computes your APY based on the compounding frequency you select, allowing you to accurately compare offers from different banks.

Taxes on CD Earnings

It's important to remember that the interest you earn on a standard CD is taxable as ordinary income at the federal and state levels (unless it is held in a tax-advantaged account like a Roth IRA). Banks will send you a Form 1099-INT at the end of the year if you earn more than $10 in interest.

You can use the Marginal Tax Rate input in our calculator to estimate your actual after-tax return. This will show you exactly how much money you get to keep after Uncle Sam takes his cut, giving you a much clearer picture of your CD's real-world profitability.

What Happens if I Withdraw Early?

CDs offer high rates because they provide banks with predictable funding. If you need to access your money before the maturity date, you will almost certainly face an early withdrawal penalty. This penalty varies by bank and term length but is typically calculated as a certain number of months of interest.

For example, withdrawing early from a 12-month CD might cost you 3 months of earned interest, while breaking a 5-year CD could cost you 6 to 12 months of interest. Always ensure you have a separate emergency fund in a liquid savings account before locking your money into a CD.

CD Laddering Strategy

To minimize the risk of needing to break a CD early while still capturing high interest rates, many investors use a "laddering" strategy. Instead of putting $10,000 into a single 5-year CD, you split the money into equal portions and buy multiple CDs with staggering maturity dates.

With this setup, one CD matures every single year. When the 1-year CD matures, you can either spend the cash if needed, or reinvest it into a new 5-year CD at the back of the ladder to keep the cycle going.