Free · No sign-up · Updated 2026 · FDIC-insured savings · APY shown
CD Calculator: what your certificate of deposit earns.
Lock in a rate, hold to maturity, and know exactly what you'll get back. Enter the deposit, rate, term, and how often interest compounds — we'll show the maturity value, the interest earned, and the true APY.
Educational tool only. This calculator and everything on this site is for general information and education. It is not investment, financial, or tax advice. CD rates and terms vary by bank, and interest is generally taxable. Always read the account terms and consult a licensed professional before making financial decisions.
How a CD calculator works
A certificate of deposit (CD) is a savings product where you agree to leave a fixed amount untouched for a set term — anywhere from a few months to five years — in exchange for a guaranteed interest rate. Because the rate is locked and the principal is FDIC-insured at member banks, a CD is one of the lowest-risk ways to grow cash you won't need right away. This calculator shows precisely what you'll have when the term ends.
The formula. Maturity value = deposit × (1 + r/n)n × t, where r is the annual rate, n is the number of compounding periods per year, and t is the term in years. The interest earned is simply the maturity value minus your deposit.
For example, $10,000 in a 12-month CD at 4.5% compounded monthly matures to about $10,459 — roughly $459 of interest. Stretch the same rate to a 5-year term and the compounding does noticeably more work, which the comparison and chart above make easy to see.
Rate vs APY: the number that matters
Two figures appear on every CD offer. The interest rate is the nominal annual rate. The APY (annual percentage yield) is what you actually earn in a year once compounding is included, so it's always a touch higher than the rate. Because APY already bakes in the compounding, comparing CDs by APY is the honest, apples-to-apples approach. This calculator reports the APY for your inputs so you can line up offers fairly.
Choosing a term
- Short terms (3–12 months) keep your money accessible sooner and let you reprice if rates rise, but usually pay a bit less.
- Longer terms (2–5 years) often lock a higher rate and let compounding run longer — valuable if you're confident you won't need the cash.
- CD ladder — splitting money across several terms — is a popular way to balance access and yield, giving you a maturing CD at regular intervals.
Recent US CD rates have hovered in the rough range of 4–5% APY, but they move with the Federal Reserve, so it pays to shop around and re-check before locking in.
Things to watch before you lock in
- Early-withdrawal penalties — taking money out before maturity usually costs several months of interest. Only commit cash you can leave alone.
- Taxes — CD interest is generally taxable in the year it's credited; this tool doesn't calculate tax, so factor that in separately.
- FDIC limits — insurance covers up to $250,000 per depositor, per institution. Spread larger sums across banks to stay fully covered.
- Inflation — a guaranteed rate still loses ground if inflation runs higher; our compound interest calculator can show the inflation-adjusted view.
Frequently asked questions
How is a CD's maturity value calculated?
A CD grows by compound interest: maturity value = deposit × (1 + r/n)n × t, where r is the annual rate, n is how many times a year interest compounds, and t is the term in years. For example, $10,000 at 4.5% compounded monthly for 12 months matures to about $10,459, earning roughly $459 in interest.
What's the difference between rate and APY?
The rate is the nominal annual interest rate. The APY (annual percentage yield) is the real yearly return after compounding is applied, so it's slightly higher than the rate. Banks advertise CDs by APY, and comparing offers by APY is the apples-to-apples way to do it.
Are CDs safe, and is the interest taxed?
CDs at FDIC-insured banks are insured up to $250,000 per depositor, per institution, which makes the principal very low risk. Interest earned is generally taxable income in the year it's credited; this calculator doesn't compute taxes, and you should consult a professional for your situation.
What if I withdraw early?
Most CDs charge an early-withdrawal penalty, often a set number of months of interest, if you take the money out before the term ends. This calculator shows the value at maturity assuming you hold the full term; check your bank's penalty terms before locking in funds you might need.
About the figures. The math uses the standard compound-interest formula for a fixed-rate deposit. Typical CD rates referenced here are illustrative of widely reported US data including the Federal Reserve and FDIC (deposit insurance up to $250,000 per depositor per institution); rates change frequently and vary by bank. This tool is for education only and is not financial, investment, or tax advice. Always read the account terms before depositing.