How Citibank calculates CD interests?

Citibank offers a CD interest calculator on its Website at https://www.citi.com/banking/current-interest-rates/cd.

This calculator uses the current APY offered by Citibank on the given deposit term length, and displays the converted APR in the output. This example confirms that the interest is compounded daily on a 365-day year basis. See the calculation below:

$\mathrm{APR}=\mathrm{365}\times ({(1+\mathrm{4.0\%})}^{{\displaystyle \frac{1}{\mathrm{365}}}}-1)=\mathrm{0.03922282044017}=\mathrm{3.92\%}$

You can verify this calculation with our online APY to APR convertor by clicking the link: "What Is the APR for an APY of 4.0% if compounded daily".

This example also confirms that the interest is calculated by using the APR and the deposit term in days on a 365-day year basis:

$\mathrm{Interest}=\mathrm{Deposit}\times ({(1+{\displaystyle \frac{\mathrm{APR}}{\mathrm{365}}})}^{\mathrm{Days}}-1)$
$\mathrm{Interest}=\mathrm{100,000}\times ({(1+{\displaystyle \frac{\mathrm{3.92\%}}{\mathrm{365}}})}^{152}-1)=\mathrm{1645.75}$

Note that the 5-month term is considered as 152 days in this example. This is not based on the calendar dates. For example, if you open your CD on 2026-01-14, a 5-month term should end on 2026-06-14, with only 151 days.

You can verify this calculation with our online CD interest calculator by clicking the link: "What Is the 152-day interest of $100,000 deposit compounded daily for an APR of 3.92% on a 365-day year basis".

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