# IS Functions

This section describes the nine worksheet functions used for testing the type of a value or reference.

Each of these functions, referred to collectively as the IS functions, checks the type of value and returns TRUE or FALSE depending on the outcome. For example, the ISBLANK function returns the logical value TRUE if value is a reference to an empty cell; otherwise it returns FALSE.

Syntax

ISBLANK(value)
ISERR(value)
ISERROR(value)
ISLOGICAL(value)
ISNA(value)
ISNONTEXT(value)
ISNUMBER(value)
ISREF(value)
ISTEXT(value)

Value     is the value you want tested. Value can be a blank (empty cell), error, logical, text, number, or reference value, or a name referring to any of these, that you want to test.

Function Returns TRUE if
ISBLANK Value refers to an empty cell.
ISERR Value refers to any error value except #N/A.
ISERROR Value refers to any error value (#N/A, #VALUE!, #REF!, #DIV/0!, #NUM!, #NAME?, or #NULL!).
ISLOGICAL Value refers to a logical value.
ISNA Value refers to the #N/A (value not available) error value.
ISNONTEXT Value refers to any item that is not text. (Note that this function returns TRUE if value refers to a blank cell.)
ISNUMBER Value refers to a number.
ISREF Value refers to a reference.
ISTEXT Value refers to text.

Remarks

• The value arguments of the IS functions are not converted. For example, in most other functions where a number is required, the text value "19" is converted to the number 19. However, in the formula ISNUMBER("19"), "19" is not converted from a text value, and the ISNUMBER function returns FALSE.
• The IS functions are useful in formulas for testing the outcome of a calculation. When combined with the IF function, they provide a method for locating errors in formulas (see the following examples).

Example 1

The example may be easier to understand if you copy it to a blank worksheet.

1. Create a blank workbook or worksheet.
2. Select the example in the Help topic.

Note   Do not select the row or column headers.

Selecting an example from Help
1. Press CTRL+C.
2. In the worksheet, select cell A1, and press CTRL+V.
3. To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Tools menu, point to Formula Auditing, and then click Formula Auditing Mode.
A B
Formula Description (Result)
=ISLOGICAL(TRUE) Checks whether TRUE is a logical value (TRUE)
=ISLOGICAL("TRUE") Checks whether "TRUE" is a logical value (FALSE)
=ISNUMBER(4) Checks whether 4 is a number (TRUE)

Example 2

The example may be easier to understand if you copy it to a blank worksheet.

1. Create a blank workbook or worksheet.
2. Select the example in the Help topic.

Note   Do not select the row or column headers.

Selecting an example from Help
1. Press CTRL+C.
2. In the worksheet, select cell A1, and press CTRL+V.
3. To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Tools menu, point to Formula Auditing, and then click Formula Auditing Mode.
A
Data
Gold
Region1
#REF!
330.92
#N/A
Formula Description (Result)
=ISBLANK(A2) Checks whether cell C2 is blank (FALSE)
=ISERROR(A4) Checks whether #REF! is an error (TRUE)
=ISNA(A4) Checks whether #REF! is the #N/A error (FALSE)
=ISNA(A6) Checks whether #N/A is the #N/A error (TRUE)
=ISERR(A6) Checks whether #N/A is an error (FALSE)
=ISNUMBER(A5) Checks whether 330.92 is a number (TRUE)
=ISTEXT(A3) Checks whether Region1 is text (TRUE)

Applies to:
Excel 2003