## Function: ISNUMBER

The Excel ISNUMBER function is an Information formula that returns TRUE if value is a number, and FALSE if not. As the name suggests, the formula asks the question "Is number?" to its argument. This way, you can test the outcome of a formula or a cell value using this...

## Function: ISLOGICAL

The Excel ISLOGICAL function is an Information formula that returns TRUE if the input is a logical value, and a FALSE result otherwise. As the name suggests, the formula asks the question "Is logical?" to the argument value. This formula can be especially useful in...

## Function: ISERROR

The ISERROR Excel function is an Information formula that returns TRUE if the target value contains an error value, and FALSE if it does not. As the name suggests, the formula asks the question "Is error?" to its argument, and returns a Boolean result. This formula...

## Function: ISERR

The ISERR Excel function is an Information formula that returns TRUE, if the reference value is an error code (except for #N/A), and FALSE otherwise. As the name suggests, the formula asks the "Is error?" question, and can be especially useful for troubleshooting and...

## Function: ISBLANK

The Excel ISBLANK function is an Information formula that returns TRUE if the reference cell is completely empty, and FALSE otherwise. As the name suggests, the formula asks the "Is X blank?" question to its argument. Although a cell must be completely "blank" for the...

## Function: CONVERT

The Excel CONVERT function is an Engineering function that converts a number between unit systems. You can convert feet into meters, pounds into kilograms, gallons into liters Fahrenheit into Celsius, and so on with this formula. In this guide, we’re going to show you...

## Function: NETWORKDAYS.INTL

The NETWORKDAYS.INTL is a Date & Time function that calculates and returns the number of business days between two given dates. The NETWORKDAYS.INTL function allows you to specify which days of the week are weekends and also use a list of holidays. In this guide,...

## Function: NETWORKDAYS

The Excel NETWORKDAYS function is a Date & Time formula that calculates the number of work days between dates. The function excludes weekends by default, and can also be set in a way to exclude a number of holidays. In this guide, we’re going to show you how to...

## Function: DAYS360

The DAYS360 function is a Date & Time formula that calculates and returns the number of days between two given dates, based on a 360-day year (12 x 30 days per month). 360-day year base is used in some accounting calculations which assumes that 1-year period is...