CD Calculator
Result Summary
No results yet
Enter your details and hit “Calculate” to see your results.
About the CD Calculator
A certificate of deposit is the rare financial product where the math is completely knowable in advance: you lock a deposit for a fixed term at a fixed APY, and the bank guarantees the outcome. That certainty is the product. This calculator gives you the exact dollar answer — interest earned and maturity value — for any deposit, rate, and term, so you can compare offers on numbers instead of marketing.
The two details that decide whether a CD beats a savings account: the term you can genuinely commit to (early withdrawal usually claws back months of interest), and whether the quoted number is APY (includes compounding — use it directly here) or APR (doesn't). Banks must advertise APY, so offers are directly comparable.
Comparing a CD against ongoing monthly investing instead? Model that with our Compound Interest Calculator
The APY Formula
Because APY already bakes in compounding, the calculation is one clean step:
Maturity Value = Deposit × (1 + APY)^years → Interest = Maturity − Deposit
Worked example: $25,000 at 4.50% APY for 18 months = 25,000 × (1.045)^1.5 = $26,706 — $1,706 in interest. Fractional years matter: notice a 6-month CD earns slightly less than half the 1-year interest, because compounding is front-loaded into time, not split evenly.
What a $10,000 CD Earns (by APY and Term)
Interest earned on $10,000 — multiply proportionally for your amount ($50,000 = 5× the cell):
| APY | 6 months | 1 year | 3 years | 5 years |
|---|---|---|---|---|
| 4.00% | $198 | $400 | $1,249 | $2,167 |
| 4.50% | $223 | $450 | $1,412 | $2,462 |
| 5.00% | $247 | $500 | $1,576 | $2,763 |
| 5.50% | $271 | $550 | $1,742 | $3,070 |
Two patterns worth noticing: at any rate, five years earns more than 5× the one-year interest (compounding), and a half-point of APY on a 5-year CD is worth roughly $300 per $10,000 — which is why shopping rates matters most on long terms.
Early Withdrawal Penalties — The Fine Print That Changes the Math
Break a CD before maturity and the bank typically forfeits a slice of interest: commonly around 3 months' worth on terms under a year, and 6–12 months' worth on longer terms (each bank sets its own schedule — it's in the account disclosure). On a young CD, the penalty can exceed interest earned so far and eat into principal.
Practical defenses: match the term to money you genuinely won't need, or build a 'CD ladder' — split the deposit across 1/2/3-year terms so a rung matures regularly. And remember no-penalty CDs exist at slightly lower APYs; this calculator prices both options so you can see what the flexibility costs.
Frequently Asked Questions
How much does a $10,000 CD make in 6 months?
At 5.00% APY, about $247; at 4.50%, about $223; at 4.00%, about $198. It's slightly less than half the 1-year figure because APY compounds over time rather than splitting evenly — the exact formula is 10,000 × (1 + APY)^0.5 − 10,000.
How much interest does a $100,000 CD make in a year?
Exactly APY × $100,000 for a 12-month term: $5,000 at 5.00% APY, $4,500 at 4.50%, $4,000 at 4.00%. Note that $100,000 sits under the $250,000 FDIC insurance limit per depositor per bank — larger amounts are commonly split across banks to stay fully insured.
How do I calculate how much I'll make on a CD?
Multiply your deposit by (1 + APY)^years, then subtract the deposit. Example: $5,000 at 4.5% APY for 3 years = 5,000 × 1.045³ = $5,706 → $706 interest. Because banks must quote APY (compounding included), you never need to know the compounding frequency — this calculator runs the same math.
Who has a 9.5% APY CD?
Nobody legitimate, in normal markets. Mainstream CD rates track the Federal Reserve's policy rate; when top nationwide CDs pay 4–5.5%, a '9.5% CD' advertisement is usually a promotional teaser on a tiny balance, a fixed annuity being marketed as a CD, or an outright scam. Verify any outlier directly on the bank's site and confirm FDIC membership.
Is CD interest taxed?
Yes — CD interest is ordinary taxable income in the U.S. for the year it's credited, even on multi-year CDs where you don't touch the money (the bank issues a 1099-INT). A 5% APY is roughly 3.9% after tax in a 22% bracket. CDs held inside IRAs defer that tax like any other IRA asset.
What happens when my CD matures?
You get a short grace period (commonly 7–10 days) to withdraw or move the money. If you do nothing, most banks auto-renew into a new CD of the same term at the current rate — which is often worse than the best available. Calendar the maturity date; the auto-renew rate is where banks earn back their generous teaser.
Are CDs worth it compared to a high-yield savings account?
A CD wins when its APY is meaningfully higher and you won't touch the money — the rate is locked even if market rates fall. Savings wins on flexibility and when rates are rising. The honest comparison: CD APY vs savings APY minus the chance you'll need the cash early (and pay the withdrawal penalty).
Are CDs FDIC insured?
Yes — CDs at FDIC-member banks are insured up to $250,000 per depositor, per bank, per ownership category (credit-union CDs get equivalent NCUA coverage). That makes the calculator's projection effectively guaranteed if you hold to maturity and stay within limits — a certainty few other yield products offer.
Sources & References
- [1]Certificates of deposit (CDs) — U.S. Securities and Exchange Commission - Investor.gov
- [2]Deposit insurance — Federal Deposit Insurance Corporation (FDIC)
Methodology. This calculator uses standard financial formulas used across the industry. It is reviewed and maintained by the Vast Calculators editorial team.
Last updated · July 2026
Disclaimer. This tool provides estimates for general informational purposes only and is not a substitute for professional financial advice. Always consult a qualified financial advisor before making decisions about your finances.