Certificate of Deposit Calculator

Estimate certificate-of-deposit interest and maturity value from principal, APY or rate, term, and compounding—presented like a bank summary. Free, print-friendly; no account, no bank login.

Estimates only | Not a bank | Not financial advice | Rates vary

Deposit details

Opening balance you plan to deposit.
APY already reflects compounding for comparison. Interest rate is the nominal annual rate. Need to convert? Use the APY calculator.
Sets term to months; you can still edit APY and term afterward.
Match your bank’s disclosure when you can. “At maturity” uses simple interest once.

Maturity estimate

Maturity value
$10,459.95
Interest earned
$459.95
Effective APY
4.50%
Term
12 months
Principal
$10,000.00

Not a live bank quote. Confirm APY, compounding, and early-withdrawal terms with your institution.

Passbook schedule

Period Interest Balance
Enter CD details to see a schedule.
Total / maturity — —

Schedule is a simplified view for planning. Your bank’s statement dates and day-count method may differ.

How it works

  1. Enter principal and rate. Use the deposit you plan to lock in, then choose APY or interest rate to match the quote you’re comparing.
  2. Set term and compounding. Months or years (try the term presets), plus daily, monthly, quarterly, annually, or interest paid only at maturity.
  3. Read interest and maturity value. See estimated interest earned, ending balance, effective APY, and a simple schedule you can print or copy.

About this CD calculator

A certificate of deposit (CD) typically pays a fixed rate for a set term. Banks and credit unions advertise APY so you can compare offers even when compounding differs. This CD calculator helps you turn a principal, rate, and term into a clear maturity estimate before you talk to an institution.

Formula and assumptions. With periodic compounding, maturity value is principal × (1 + r/n)n×years, where r is the annual rate as a decimal and n is compounding periods per year. If you choose “at maturity,” simple interest is used once: principal × (1 + r × years). The estimate assumes you hold the CD to maturity, the rate you entered does not change, and a simplified day-count (year fractions from months/years you type). It does not include early-withdrawal penalties, fees, or taxes.

This site is not a bank and does not claim FDIC insurance for any specific deposit you may open elsewhere. Always confirm APY, compounding, and disclosure with your institution.

  • Works offline in your browser after the page loads
  • No signup and no bank login
  • Optional local save of your last inputs on this device only

Frequently asked questions

How does a CD calculator work?

You enter the deposit amount (principal), an APY or interest rate, the term, and how often interest compounds. The tool applies compound interest (or simple interest if interest is paid only at maturity) to estimate interest earned and the balance at maturity.

What is the difference between APY and interest rate on a CD?

The interest rate is the nominal annual rate before compounding frequency is fully reflected. APY (annual percentage yield) already includes the effect of compounding over a year, so it is useful for comparing offers. This calculator lets you enter either. To convert between them, use the APY calculator.

How is CD compound interest calculated?

With periodic compounding, maturity value is principal × (1 + r/n)n×years, where r is the annual rate as a decimal and n is compounding periods per year. If interest is paid only at maturity, simple interest is used: principal × (1 + r × years).

Why are early withdrawal penalties not included?

Banks set early-withdrawal penalties differently, and the rules are specific to each disclosure. This estimator assumes you hold the CD to maturity so the math stays clear. Check your institution for penalty terms before you withdraw early.

Does this tool open a CD or show live bank rates?

No. Free CD Calculator only estimates results from numbers you type. It is not a bank, does not open accounts, and does not quote live rates. Always confirm terms with your institution.

Do my deposit numbers get sent to a server?

No. Math runs in your browser. Optional localStorage may keep your last inputs on your device only.