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CD Calculator

See what a certificate of deposit is worth at maturity. Enter the deposit, rate, compounding frequency, term, and tax to get the end balance, interest, and accumulation schedule.

ExampleSample values — edit any field to see your result.

$
%

The annual rate the CD pays. Banks usually quote APY; choose Annually (APY) when that is what you have, or Monthly (APR) for a nominal monthly rate.

Annually (APY) treats the rate as a yearly yield. Monthly (APR) treats it as a nominal rate compounded monthly.

%

Applied to the interest earned each month, not to the deposit. Enter 0 if the CD is in a tax-deferred or tax-free account, or if you only want the pre-tax figure.

Results update as you type.

End Balance

$11,576.25

Estimated result

Total Interest
$1,576.25

Balance breakdown

Initial deposit 86%, Interest 14%
  • Initial deposit86%
  • Interest14%

Accumulation schedule

PeriodDepositInterestEnding balance
Year 1$10,000.00$500.00$10,500.00
Year 2$0.00$525.00$11,025.00
Year 3$0.00$551.25$11,576.25
End Balance$11,576.25

See what a certificate of deposit is worth at maturity. Enter the opening deposit, the annual rate, how often interest compounds, the term in years and months, and an optional marginal tax rate. You get the end balance, the interest earned, and a month-by-month accumulation schedule.

Formula

A CD compounds a single deposit — there are no ongoing contributions. The stated annual rate r is first converted to an effective annual rate at your chosen frequency, then to an equivalent monthly rate so every month of the schedule is consistent:

APY  = (1 + r/n)^n − 1          (continuous: e^r − 1)
i    = (1 + APY)^(1/12) − 1

Each month the CD credits balance × i of interest. If you enter a tax rate, that fraction of the month's interest is withheld and the rest is reinvested. Annually (APY) at 5% therefore still ends each year 5% higher, even though the table shows monthly growth.

Banks almost always quote CDs as APY. Leave Compound on Annually (APY) unless the rate you have is clearly a nominal APR.

APY vs. APR at 5% for 3 years on $10,000

CompoundEquivalent APYEnd balance
Annually (APY)5.000%$11,576.25
Semiannually5.063%$11,596.93
Quarterly5.095%$11,607.55
Monthly (APR)5.116%$11,614.72
Continuously5.127%$11,618.34

Examples

$10,000 at 5% APY for 3 years

A $10,000 CD at 5% compounded annually grows to $11,576.25 — $1,576.25 of interest. Year 1 ends at $10,500, year 2 at $11,025, year 3 at $11,576.25.

Same CD taxed at 25%

The same CD with a 25% marginal tax rate finishes at $11,160.92. Gross interest is $1,547.90 and tax is $386.97, so $1,160.92 of interest stays in the account. Tax is taken each month, which also slows later compounding.

A 6-month CD

The same $10,000 at 5% APY for six months grows to $10,246.95. Short terms are shown month by month rather than as a full year.

Frequently asked questions

What is a certificate of deposit?
A CD is an agreement to leave money on deposit for a fixed term in exchange for a stated interest rate. Typical terms run from three months to five years. CDs sit on the low-risk, low-return end of the spectrum — usually paying more than a savings account, but much less than the long-run stock market.
What is the difference between APY and APR?
APY (annual percentage yield) already includes compounding, so a 5% APY grows the balance by exactly 5% in a year. APR is a nominal rate; monthly APR of 5% compounds 12 times and yields about 5.116%. Banks advertise CDs in APY. Use Annually (APY) when that is the number on the offer, or Monthly (APR) if you only have a nominal monthly rate.
How does the tax rate work?
CD interest is taxable as ordinary income in the year it is credited, even if you cannot withdraw it yet. This calculator withholds tax from each month's interest at your marginal rate before the leftover is reinvested. Enter 0 if the CD sits in a tax-deferred IRA, a Roth IRA, or if you only want the pre-tax figure. Total interest is the amount credited before tax; the end balance is after tax.
Are CDs FDIC-insured?
CDs from FDIC-insured banks are insured up to $250,000 per depositor, per bank. Credit-union share certificates have equivalent NCUA coverage. To keep more than $250,000 insured, split deposits across more than one insured institution.
What is a CD ladder?
Instead of locking everything into one long CD, you split the money across several CDs that mature at staggered dates (for example 1, 2, and 3 years). Each maturity frees cash to spend or to roll into a new CD at the current rate, which adds flexibility if you might need the money or if rates are rising.

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