CD Calculator
A certificate of deposit locks in a fixed rate for a set term, so the payout is known in advance. Adjust your deposit, the APY, and the term in months to see what you will collect at maturity. The numbers refresh as you slide.
A $10,000 CD at 5% APY for 12 months matures at $10,500 — $500 in guaranteed interest. CDs lock your rate, so they shine when rates are high and falling.
Worked examples
Real results from this calculator, computed for a few common scenarios. Move the sliders above to run your own numbers.
| Deposit = $100,100 | A $100,100 CD at 5% APY for 12 months matures at $105,105 — $5,005 in guaranteed interest. CDs lock your rate, so they shine when rates are high and falling. |
| Deposit = $250,100 | A $250,100 CD at 5% APY for 12 months matures at $262,605 — $12,505 in guaranteed interest. CDs lock your rate, so they shine when rates are high and falling. |
| Deposit = $400,000 | A $400,000 CD at 5% APY for 12 months matures at $420,000 — $20,000 in guaranteed interest. CDs lock your rate, so they shine when rates are high and falling. |
Your next step
How this math works
The maturity value is your deposit multiplied by one plus the APY, raised to the power of the term in months divided by twelve. The interest earned is simply that maturity value minus your original deposit.
Because the rate is locked at purchase, certificates of deposit shine when rates are high and expected to fall. You hold the high rate even after new CDs start paying less.
Common questions
What does APY mean?
APY is the annual percentage yield, the rate of return over a year once compounding is included. It is the figure banks advertise for certificates of deposit.
Can I take my money out early?
Usually yes, but most certificates of deposit charge an early withdrawal penalty, often several months of interest. This tool assumes you hold the CD to maturity.
Is the interest taxable?
Yes. Interest from a certificate of deposit is generally taxed as ordinary income in the year it is earned, even if you do not withdraw it.
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