What does the CD Calculator compute?

It computes the maturity value, interest earned, and APY of a certificate of deposit from the deposit amount, annual percentage rate, term in months, and compounding frequency, using the compound-interest formula.

What is the difference between APR and APY on a CD?

APR is the nominal annual rate a bank quotes before compounding. APY is the effective annual yield after compounding is applied, so it is usually slightly higher than the APR — the CD Calculator shows both.

How does compounding frequency change the CD Calculator's result?

More frequent compounding (daily vs. monthly vs. annually) lets interest earn interest more often, which raises the APY slightly for the same nominal APR, and increases the final maturity value a small amount.

Can I use the CD Calculator for a CD term shorter than a year?

Yes. Enter the term in months — a 3-month or 6-month CD works the same way as a multi-year one, since the formula scales the exponent by months divided by 12.

Does the CD Calculator account for early-withdrawal penalties?

No. It calculates the maturity value assuming the CD is held for its full term. Early withdrawal typically forfeits some interest as a penalty, which this tool does not subtract.

CD Calculator Online

Calculate the maturity value, interest earned, and APY of a certificate of deposit in your browser. Estimates only, not financial advice.

The CD Calculator runs entirely in your browser. The deposit amount, rate, and term you enter never leave your device and nothing is uploaded to ArrayKit. Results are estimates only and not financial advice.

Open the Compound Interest Calculator

About CD Calculator

CD Calculator works out the maturity value, interest earned, and annual percentage yield (APY) of a certificate of deposit before you lock in your money. Enter the deposit amount, the annual percentage rate (APR) the bank quotes, the term in months, and how often interest compounds, and it applies the compound-interest formula A = P × (1 + r/n)^(n×t) to show exactly what the CD will be worth at maturity. Because interest compounds on interest already earned, the effective APY is usually a little higher than the stated APR — this tool shows both so you can compare offers from different banks on equal footing. It is useful when you are shopping for CD rates, comparing a 6-month CD against a 12-month or 5-year term, or checking a bank's advertised APY before you commit funds. These are estimates only and not financial advice — actual bank terms, minimum balances, and early-withdrawal penalties vary, so confirm figures with your financial institution. Everything runs locally in your browser.

Features

Computes maturity value using the compound-interest formula A = P(1 + r/n)^(n×t)
Shows interest earned separately from the total maturity value
Calculates the effective APY so you can compare CDs with different compounding schedules
Choose annual, quarterly, monthly, or daily compounding to match a bank's actual terms
Term entered in months so short CDs (3, 6, 9 months) are as easy to model as multi-year ones
Copy button for a plain-text summary of the deposit, rate, term, and results
Clear error message when the deposit, rate, or term is missing or invalid
Runs entirely in your browser with no deposit figures sent anywhere

How to use the CD Calculator

Enter the deposit amount you plan to put into the CD
Enter the annual percentage rate (APR) the bank is offering
Enter the CD term in months and choose the compounding frequency
Read the maturity value, interest earned, and APY, and copy the summary if needed

Example

Input

$10,000, 5% APR, 12 mo

Output

Maturity: $10,511.62
APY: 5.12%

Common errors & troubleshooting

The APR was entered as 0.05 instead of 5, giving a maturity value that looks almost unchanged. — Enter the annual rate as a percentage number, such as 5 for 5%, not as a decimal fraction.
The term was entered in years instead of months, producing a maturity value far larger than expected. — The CD Calculator expects the term in months — a 1-year CD is 12, a 5-year CD is 60.
The result doesn't match the bank's advertised APY exactly. — Confirm which compounding frequency the bank uses (daily, monthly, or quarterly) and match it in the CD Calculator — different compounding schedules produce slightly different APYs for the same APR.
An early withdrawal changed the actual payout. — This calculator assumes the CD is held to full maturity; early-withdrawal penalties reduce the real payout and are not modeled here.

Frequently asked questions

What does the CD Calculator compute?: It computes the maturity value, interest earned, and APY of a certificate of deposit from the deposit amount, annual percentage rate, term in months, and compounding frequency, using the compound-interest formula.
What is the difference between APR and APY on a CD?: APR is the nominal annual rate a bank quotes before compounding. APY is the effective annual yield after compounding is applied, so it is usually slightly higher than the APR — the CD Calculator shows both.
How does compounding frequency change the CD Calculator's result?: More frequent compounding (daily vs. monthly vs. annually) lets interest earn interest more often, which raises the APY slightly for the same nominal APR, and increases the final maturity value a small amount.
Can I use the CD Calculator for a CD term shorter than a year?: Yes. Enter the term in months — a 3-month or 6-month CD works the same way as a multi-year one, since the formula scales the exponent by months divided by 12.
Does the CD Calculator account for early-withdrawal penalties?: No. It calculates the maturity value assuming the CD is held for its full term. Early withdrawal typically forfeits some interest as a penalty, which this tool does not subtract.
Is my deposit information sent anywhere when I use the CD Calculator?: No. The CD Calculator runs entirely in your browser. The deposit amount, rate, and term you enter never leave your device and are not uploaded to ArrayKit.

Related tools

Compound Interest Calculator — Project savings growth with compound interest and optional regular contributions.
Savings Calculator — See how a starting balance plus regular deposits grow with interest over time.
Bond Calculator — Calculate a bond price, current yield and yield to maturity.
Investment Calculator — Solve for the ending amount, return, contribution or time of an investment.
Interest Calculator — Calculate simple or compound interest and the total from principal, rate and time.
Future Value Calculator — Find the future value of a present sum or a stream of payments.