Enter the deposit, the APY from the CD offer and the term, and this CD calculator shows what the certificate of deposit would be worth at maturity and how much interest it would earn along the way. Because it works from APY — the effective yearly yield, compounding included — there is no separate compounding setting to guess at. It also shows the maturity date, so you can judge whether locking the money away for that long fits your plans. There is no sign-up and nothing to submit — the results update as you type.
Use the APY from the CD offer, not the plain interest rate — APY already includes compounding, which is why this calculator needs nothing else.
deposit plus interest
over the full term
the amount you put in
at 5% APY
Opened today, this CD would mature around November 5, 2027 at $10,500.00. Withdrawing before that date usually triggers an early withdrawal penalty, so only lock away money you are confident you will not need during the term.
How the estimate works: because APY is the effective annual yield, the deposit is grown by that rate for the fraction of a year the term covers — deposit multiplied by (1 + APY) raised to the power of months divided by 12. It assumes the APY stays fixed for the whole term, the money stays in until maturity, and no tax or early withdrawal penalty applies — a bank may credit interest on its own schedule, so its final figure can differ by a few cents.
How to use this calculator
- Enter the amount you plan to deposit.
- Enter the APY from the offer — not the plain interest rate, if both are shown.
- Set the term in months, typing it or using the quick-select buttons.
- Read the value at maturity and the interest earned, and note the maturity date.
- Try a shorter and a longer term with the same deposit to see what the extra time adds.
APY vs APR: what is the difference?
APY stands for annual percentage yield. It is the effective return on a deposit over a year, including compounding — the effect of earning interest on interest you have already earned. If a CD quotes 5% APY, $10,000 in it for a full year grows to $10,500, whatever the compounding schedule underneath. That makes APY the right number for comparing deposit offers.
APR stands for annual percentage rate. It expresses a yearly rate without compounding built in. You will meet APR most often on the borrowing side — loans and credit cards — where it describes the cost of the debt. A savings product may show both a plain interest rate and an APY; when it does, the APY is the higher, more complete figure, and it is the one this calculator uses.
How a CD works
A certificate of deposit is a savings product with a fixed term: you deposit money for an agreed number of months, the bank pays a fixed yield for that period, and you get the deposit plus interest back at maturity. In exchange for leaving the money untouched, a CD usually pays more than an everyday savings account — and the trade-off is the early withdrawal penalty if you need the money sooner. That makes CDs a fit for money with a known future date, such as a planned purchase next year, rather than for your emergency fund, which needs to stay instantly available.
A worked example
Deposit $10,000 at 5% APY for 12 months and the maths is clean: $10,000 multiplied by 1.05 is $10,500.00 at maturity, so the interest earned is exactly $500.00. Shorten the term to 6 months at the same APY and the value is $10,000 multiplied by 1.05 raised to the power of one half, which comes to $10,246.95 — interest of $246.95. Notice it is a little more than half of the full-year interest: that small extra is compounding at work, and it is exactly what APY captures.
Before you open a CD
- Compare APY to APY across offers, and check the minimum deposit each one needs.
- Read the early withdrawal penalty in the terms before you open it, not after.
- Match the term to a real date — money needed sooner belongs somewhere you can reach it.
- Check what happens at maturity: many CDs renew automatically into a new term if you do nothing.
- Keep your emergency fund separate and accessible; a CD is for money you can lock away.
More calculators & tools
To see compounding without a fixed term, try the Compound Interest Calculator. To work out how much safety-net money to keep accessible in the first place, use the Emergency Fund Calculator and read our guide on how much to keep in an emergency fund and where to keep it. The Inflation Calculator shows what rising prices do to the value of savings over time, all the tools live on the calculators hub, and our budgeting guides cover where saving fits in a monthly plan.
This calculator provides estimates for general education only and is not financial, legal, or tax advice. Results assume a fixed APY, no early withdrawal and no tax deducted; a bank may credit interest on its own schedule and its terms set the actual outcome. For advice about your own situation, talk to a qualified professional.
Frequently Asked Questions
What is the difference between APY and APR on a CD?+
APY (annual percentage yield) is the effective yearly return including compounding — the interest your interest earns — so it is the number that tells you what a deposit actually grows by in a year. APR (annual percentage rate) is a yearly rate without compounding built in, and you meet it most often as the cost of borrowing on loans and cards. On savings products, compare APY to APY: two CDs with the same plain rate can have different APYs if they compound differently.
How is CD interest calculated?+
This calculator uses the APY directly, because APY already includes compounding: value at maturity equals deposit multiplied by (1 + APY) raised to the power of term in years, so a term of 6 months uses a power of 0.5. That is why $10,000 at 5% APY for a full year comes to exactly $10,500, and for 6 months it comes to $10,246.95. A bank may credit interest monthly, quarterly or at maturity, so its final figure can differ by a few cents.
What happens if I withdraw from a CD early?+
Banks typically charge an early withdrawal penalty, often expressed as a set number of months of interest, and the exact penalty is in the terms of the CD you open. On a short-held CD the penalty can take back some or all of the interest earned, and in some cases part of the deposit. That is why a CD suits money you are confident you will not need until the maturity date.
Are CDs insured?+
At an FDIC-insured bank, deposits including CDs are insured up to $250,000 per depositor, per insured bank, for each account ownership category. At a federally insured credit union, the same $250,000 limit applies through the NCUA. Cover applies if the institution fails — it does not protect against early withdrawal penalties or inflation.
Is CD interest taxed?+
Generally, yes. Interest earned on a CD is usually taxed as ordinary income in the year it is credited to you, even if the CD has not matured yet and even if you leave the money in. Your bank reports it to you for your tax return. Rules vary with your situation, so check the current guidance or a tax professional for anything beyond the general picture.
Does this calculator store or send my data?+
No. The calculator runs entirely in your browser. Nothing you type is sent to a server, saved, or shared — refresh the page and it is gone.