Saving & investing

Certificate of deposit (CD): Definition, Formula and Example

A certificate of deposit is a time deposit that generally holds money for a specified term under stated interest and withdrawal conditions.

Scope: General financial concept; examples are hypothetical.

Other names and related labels: CD; Time deposit.

How it works

Traditional bank CDs often offer a fixed rate, while other structures may have variable or callable features. Withdrawing early can reduce earnings or principal through a penalty. A brokered CD sold before maturity may receive a market price rather than its original deposit amount.

For a fixed rate with reinvested interest: maturity value = principal × (1 + rate per period)^periods

Check APY, interest-crediting frequency, maturity, renewal terms and withdrawal rules. Deposit-insurance eligibility and limits depend on the institution and ownership category.

$5,000 for two years at 4%, compounded annually

Assume interest remains in the CD until maturity.

  1. Year 1: $5,000 × 1.04 = $5,200.
  2. Year 2: $5,200 × 1.04 = $5,408.

Maturity value is $5,408, including $408 of interest before tax.

Fixed rate, no early withdrawal, no fees, no automatic-renewal period.

Try these example inputs

A deposit product is not automatically risk-free in every form

Insurance does not cover every issuer, every amount or a loss from selling a brokered CD at a lower market price. Do not treat a hypothetical rate in the calculator as a current bank offer.

Explore with a calculator

  • CD Calculator

    Model maturity value, compounding and an entered interest-tax assumption.

Sources and checks

Calculation methodology and review status · All glossary terms