CD (Certificate of Deposit) / Fixed Deposit (FDR) Calculator
Calculate CD interest earnings, maturity balance, compounding yield, and early withdrawal penalties for bank certificates of deposit.
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A Certificate of Deposit (CD), known internationally as a Fixed Deposit Receipt (FDR) or Term Deposit, is a low-risk financial instrument issued by commercial banks and credit unions that pays a guaranteed fixed interest rate in exchange for locking up capital for an agreed-upon term.
1. Mathematical Compounding Formulas (APR vs. APY)
When interest is quoted as a nominal Annual Percentage Rate (APR) with periodic compounding ($n$ times per year), the maturity value $A$ is calculated as:
Where $P$ is the principal deposit, $r$ is the decimal annual rate, $n$ is compounding frequency per year (365 for daily, 12 for monthly), and $t$ is duration in years. The effective Annual Percentage Yield (APY) reflects this compounding boost:
When banks directly quote the APY, maturity value simplifies directly to: $A = P(1 + \text{APY})^t$.
2. Practical Worked Example: $20,000 in a 3-Year CD at 4.85% APY
Suppose an investor places $20,000 into a 3-Year (36-month) CD offering 4.85% APY with daily compounding:
- Maturity Balance: $A = \$20,000 \times (1 + 0.0485)^3 = \$20,000 \times 1.152646 = \mathbf{\$23,052.92}$.
- Total Guaranteed Interest: $$23,052.92 - \$20,000 = \mathbf{\$3,052.92}$ (+15.26% total return).
- Average Monthly Passive Income: $$3,052.92 \div 36 = \mathbf{\$84.80}$ per month.
- Early Withdrawal Penalty Simulation: If redeemed after 18 months under a 6-month interest penalty clause:
- Accrued interest at Month 18: $\$1,489.15$
- Penalty (6 months interest): $6 \times \$84.80 = \$508.80$
- Net Payout Received: $$20,000 + (\$1,489.15 - \$508.80) = \mathbf{\$20,980.35}$.
3. Cash Equivalents Comparison: CD vs. HYSA vs. Treasury Bills
| Feature | Certificate of Deposit (CD) | High-Yield Savings (HYSA) | U.S. Treasury Bills (T-Bills) |
|---|---|---|---|
| Rate Guarantee | Fixed for entire term (Locked) | Variable (Fluctuates with Fed rate) | Fixed discount yield to maturity |
| Liquidity & Access | Locked until maturity (Early penalty) | Instant (Up to 6 withdrawals/mo) | Tradable on secondary bond market |
| Insurance & Backing | FDIC / NCUA up to $250,000 | FDIC / NCUA up to $250,000 | Backed by full faith of U.S. Govt |
| State & Local Taxation | Subject to Federal + State tax | Subject to Federal + State tax | 100% exempt from state & local tax |
🔗 Fixed Income & Savings Cross-References
Certificates of Deposit (CDs) and Fixed Deposit Receipts (FDR) lock in a guaranteed fixed annual percentage yield (APY) for a predetermined maturity duration. Visit our 💰 Financial Hub to compare fixed yields against equity growth.
Convert nominal rates into effective APY or model multi-decade compound interest accumulation with the calculators below.
Frequently Asked Questions (CD Calculator)
A CD ladder divides your savings into equal tranches invested across varying maturities (e.g., 6 months, 1 year, 2 years, 3 years). As each CD matures, you roll it into a long-term CD at the highest prevailing rate, providing continuous liquidity every few months without sacrificing yield.
Yes. If you withdraw funds very shortly after opening the CD (e.g., within the first 30 days) and have not yet accrued enough interest to cover the contractual penalty (such as 90 or 180 days of interest), the bank will deduct the remaining penalty from your principal balance.
Banks provide a 7-to-10-day grace period upon maturity. During this window, you can withdraw your principal and accrued interest, add or withdraw funds, or transfer into another product. If no action is taken, most institutions automatically roll the balance into a new CD of the same term at current market rates.
Interest earned on standard CDs is taxable in the calendar year it accrues, even if it remains locked inside the CD until a future maturity year. Your bank issues an IRS Form 1099-INT annually reporting all interest earned.