CD Calculator
Calculate Certificate of Deposit (CD) returns with our comprehensive CD calculator. This tool helps you understand how your money will grow over time with different CD terms, interest rates, and compounding frequencies. Enter your initial deposit, interest rate, and term to see the final value, total interest earned, monthly interest, and APY (Annual Percentage Yield). The calculator shows growth over time with visual charts and helps you compare different CD options. Perfect for planning savings, comparing investment options, or understanding compound interest. All calculations happen instantly in your browser with complete privacy—no data is stored or transmitted.
CD Calculator
How it works: This calculator calculates the growth of a Certificate of Deposit (CD) using compound interest. The formula is: A = P(1 + r/n)^(nt), where A is the final amount, P is the principal, r is the annual interest rate, n is the number of times interest is compounded per year, and t is the number of years. APY (Annual Percentage Yield) shows the effective annual rate including compounding effects.
What Is a CD Calculator?
A CD calculator (certificate of deposit calculator) computes the interest you earn and the maturity value of a CD given a principal amount, APY, term length, and compounding frequency. CDs are time-deposit accounts offered by banks and credit unions that pay a fixed interest rate in exchange for locking your money for a set term — from 3 months to 5 years. They are FDIC-insured up to $250,000, making them one of the safest ways to earn a guaranteed return. This calculator helps you compare CD options side-by-side and decide whether a CD beats your current savings account rate.
How to Calculate CD Interest
CD maturity value uses the compound interest formula: A = P × (1 + r/n)^(n×t), where P is your deposit, r is the annual rate (as a decimal), n is compounding periods per year (usually daily or monthly), and t is years. Most CDs compound daily, so n = 365. For a $20,000 CD at 5.10% APY compounded daily for 1 year: A = $20,000 × (1 + 0.051/365)^365 = $21,020. Interest earned: $1,020.
Worked Example: David Compares CDs vs. HYSA
David has $30,000 in a high-yield savings account at 4.50% APY and is offered a 1-year CD at 5.20% APY.
1-year CD at 5.20% APY: $30,000 → $31,560 (+$1,560)
HYSA at 4.50% APY: $30,000 → $31,350 (+$1,350)
CD earns $210 more — but money is locked for 12 months
Early withdrawal penalty: typically 3–6 months of interest (~$390–$780 forfeited)
CD Term Comparison — $20,000 Deposit at 2025 Typical Rates
| CD Term | Typical APY | Maturity Value | Interest Earned | Best For |
|---|---|---|---|---|
| 3-month | 4.75% | $20,238 | $238 | Parking cash short-term |
| 6-month | 5.00% | $20,500 | $500 | Known expenses in 6 months |
| 1-year | 5.10% | $21,020 | $1,020 | Known annual expenses |
| 2-year | 4.80% | $21,979 | $1,979 | Medium-term savings |
| 5-year | 4.25% | $24,648 | $4,648 | Long-term guaranteed return |
CD Ladder Strategy
A CD ladder splits your money across multiple CD terms to balance higher rates (longer terms) with regular liquidity (shorter terms maturing each year). Example: $40,000 split into four $10,000 CDs maturing in 1, 2, 3, and 4 years. When each matures, reinvest into a 4-year CD. After 4 years, you have one CD maturing every year at 4-year rates. This earns more than a savings account while giving you access to $10,000 per year without penalties.
Tips for CD Investing
Compare online banks and credit unions — they typically offer 0.5–1.5% higher APYs than big national banks. Confirm whether the rate is APR or APY (APY accounts for compounding; higher). Check early withdrawal penalties before committing — 3-month penalties on short CDs are usually minor, but 12-month penalties on 5-year CDs can wipe out gains if you exit early. CDs are ideal for money you know you won't need for the term length: tax refunds earmarked for a specific purchase, house down payment funds, or capital you want protected from market risk.
Frequently Asked Questions About CDs
Are CDs FDIC insured?
Yes. CDs at FDIC-member banks are insured up to $250,000 per depositor per ownership category. At NCUA-member credit unions, coverage is the same under NCUA insurance. This makes CDs one of the safest savings vehicles — your principal is guaranteed regardless of market conditions.
What happens if I withdraw a CD early?
Most CDs charge an early withdrawal penalty, typically equal to 3–6 months of interest on short-term CDs and 6–12 months on longer-term CDs. If you withdraw a 2-year CD after 6 months with a 6-month penalty, you may earn little or nothing. Some banks offer no-penalty CDs with slightly lower rates.
Is a CD better than a high-yield savings account?
It depends on whether you can commit to the term. CDs typically pay 0.25–0.75% more than HYSAs but lock your money. If rates rise after you open a CD, you're locked in at the lower rate. HYSAs are variable — rates move with the Fed funds rate. For money you definitely won't need, a CD is usually better.
What's the difference between APR and APY on a CD?
APR is the stated rate. APY includes compounding. A CD with a 5.00% APR compounded daily has a 5.13% APY. Banks are required to disclose APY for deposit accounts. Always compare APY when shopping CDs.
Can I add money to a CD after opening?
Standard CDs don't allow additional deposits. Some banks offer ‘add-on CDs’ that let you deposit more during the term — but they usually pay lower rates than standard CDs. If you want the ability to add funds regularly, a HYSA or money market account is more appropriate.
How are CD earnings taxed?
CD interest is taxed as ordinary income in the year it is credited to your account (or in the year of maturity for shorter-term CDs). Even if you haven't withdrawn the money, the bank reports interest to the IRS on Form 1099-INT. If your CD spans multiple tax years, interest is prorated. CDs in IRAs grow tax-deferred.