CD Calculator
Use this free CD interest calculator to estimate your certificate of deposit's maturity balance, total interest earned and annual return. Enter your deposit, the advertised APY and the term, and you also get an illustrative monthly-equivalent schedule you can download. Every formula we use is listed on the methodology page.
Designed for standard fixed-rate CDs where interest remains on deposit until maturity. It does not model mandatory interest payouts, stepped or variable rates, fees, taxes, or early-withdrawal penalties.
Figures are pre-tax estimates. Actual bank earnings may vary slightly due to term dates, calculation methods, and rounding.
Show the math for your inputs
APY already includes compounding, so the compounding frequency your bank uses does not change these numbers. Full derivation, sources, and rounding rules are on the methodology page.
Illustrative monthly-equivalent growth schedule
This schedule evenly models the advertised APY across monthly intervals. It may not match your bank's actual daily accrual or interest-crediting schedule.
| Month | Modeled growth this month | Modeled growth to date | Balance |
|---|---|---|---|
| 1 | $36.75 | $36.75 | $10,036.75 |
| 2 | $36.88 | $73.63 | $10,073.63 |
| 3 | $37.02 | $110.65 | $10,110.65 |
| 4 | $37.15 | $147.80 | $10,147.80 |
| 5 | $37.29 | $185.10 | $10,185.10 |
| 6 | $37.43 | $222.52 | $10,222.52 |
| 7 | $37.57 | $260.09 | $10,260.09 |
| 8 | $37.70 | $297.79 | $10,297.79 |
| 9 | $37.84 | $335.64 | $10,335.64 |
| 10 | $37.98 | $373.62 | $10,373.62 |
| 11 | $38.12 | $411.74 | $10,411.74 |
| 12 | $38.26 | $450.00 | $10,450.00 |
How this calculator works
APY (Annual Percentage Yield) already includes the effect of compound interest, so the estimate uses this formula:
value at maturity = deposit × (1 + APY)^(term in years)
Under SaverGrid's assumption that 12 months equals one year, a $10,000 CD at 4.50% APY produces an estimated maturity value of $10,450 before tax. APY already includes compounding, so applying a nominal-rate compounding formula directly to it would double-count compounding and overstate estimated earnings. If you start from thenominal rate, you can convert between the two under "Advanced options" above. Your bank's result may vary slightly based on dates, rounding, and account terms. The details are on the methodology page.
Worked examples
A few common scenarios, calculated with the formula above. Click one to load it into the calculator and adjust from there.
| Scenario | Estimated interest | Estimated maturity value |
|---|---|---|
| $10,000.00 at 4.00% APY for 1 year | $400.00 | $10,400.00 |
| $10,000.00 at 4.50% APY for 1 year | $450.00 | $10,450.00 |
| $25,000.00 at 4.50% APY for 1 year | $1,125.00 | $26,125.00 |
| $50,000.00 at 4.25% APY for 2 years | $4,340.31 | $54,340.31 |
| $10,000.00 at 4.00% APY for 6 months | $198.04 | $10,198.04 |
| $10,000.00 at 3.50% APY for 5 years | $1,876.86 | $11,876.86 |
Frequently asked questions
How is CD interest calculated?
APY (Annual Percentage Yield) already includes the effect of compounding. Under SaverGrid's assumption that 12 months equals one year, a $10,000 CD at 4.50% APY produces an estimated maturity value of $10,450 before tax. Your bank's result may vary slightly based on dates, rounding, and account terms.
Does compounding frequency change my CD earnings?
APY already reflects compounding, so SaverGrid does not apply a compounding frequency again when estimating earnings. Compounding frequency matters when converting between APY and a nominal interest rate. Your bank's actual result may still vary with dates, rounding, and account terms.
How much does a $10,000 CD earn in a year?
At 4.50% APY, a 12-month CD on $10,000 earns about $450 in interest, for a total of about $10,450 at maturity. At 5.00% APY it earns about $500. The final figure your bank credits can vary slightly with dates, rounding, and account terms.
Does CD interest compound?
It depends on the CD terms. APY already reflects the effect of compounding for an account where interest remains on deposit, which is why this estimate starts from APY. Check the account disclosure for the bank's calculation, crediting, and payout terms.
Is CD interest based on APY or the interest rate?
Account disclosures distinguish the nominal annual interest rate from APY, which reflects compounding. SaverGrid uses APY to estimate growth under its stated assumptions. To convert between the two rates, open Advanced options in the calculator above.
How do you calculate CD maturity value?
Multiply your deposit by (1 + APY) raised to the power of the term in years. For example, a $25,000 CD at 4.50% APY for 2 years is 25,000 × 1.045², which comes to about $27,301 before tax.
Are CD earnings taxed?
CD interest is generally taxable for federal income-tax purposes. The timing of when you report it depends on the CD's term and how the bank reports the interest. CDs with maturities longer than one year may involve annual original-issue-discount reporting. State tax treatment varies. SaverGrid results are pre-tax estimates.
What this calculator doesn't cover
- Early-withdrawal penalties. Breaking a CD before maturity typically costs several months of interest. A dedicated penalty calculator is coming soon.
- Taxes. Results are pre-tax; reporting timing and state treatment vary.
- Fees. Account or maintenance fees are not deducted.
- Mandatory interest payouts. The model assumes interest remains deposited through maturity.
- Rate changes. Standard CDs lock the rate for the whole term, but bump-up and variable-rate CDs behave differently.