CD Calculator (Certificate of Deposit)
See what a certificate of deposit will be worth at maturity. Enter your deposit, APY and term to get the ending value and interest — compared to the national-average CD rate.
Example: with Deposit amount $10,000 · APY 4.5% · Term 12 months · Compounding Annually (APY) → Value at maturity: $10,450.
- Interest earned$450
- APY applied4.50% APY
- After-tax interest$450
Computed by the calculator below using its default values. Change any input to see your own numbers.
How you compare
\ud83c\udfe6 Compare today\u2019s top CD rates
Learn moreHow CDs work
A certificate of deposit locks your money for a fixed term in exchange for a fixed, usually higher, APY. You generally cannot withdraw early without a penalty, so CDs suit money you will not need until maturity. Because the rate is fixed, the maturity value is known the day you deposit. Online banks often pay far more than the national average.
How it’s calculated & sources
Maturity value = deposit × (1 + APY)^(term in years). Interest = maturity value − deposit. APY already reflects compounding, so it is applied directly. Compared to the FDIC national-average 1-year CD rate.
When a compounding frequency other than annually is selected, the entered rate is treated as a nominal annual rate and compounded n times per year — semiannually (n=2), quarterly (n=4), monthly (n=12), or continuously (e^(rate × years)) — and the “APY applied” output shows the resulting effective annual yield. After-tax interest subtracts your entered marginal tax rate (0% by default) from the pre-tax interest earned; it does not change the maturity value or interest-earned figures above, which always show pre-tax results.
Benchmark: FDIC national average 1-year CD about 1.8 percent; top online CDs pay roughly 4 to 5 percent APY (2026).
Results update as you type and are general estimates, not personalized advice. Verify with a professional.
Frequently asked questions
What happens if I withdraw early?
Most CDs charge an early-withdrawal penalty of a few months interest, which can eat into or exceed what you earned.
Is a CD better than a high-yield savings account?
A CD locks the rate so it will not drop, but savings stays liquid. Use a CD for money with a known time horizon.
Are CDs safe?
CDs at FDIC-insured banks are covered up to $250,000 per depositor, per bank, so principal is protected within limits.