ISBLANK, ISNUMBER, ISTEXT and ISERROR functions in Excel

The IS functions test what kind of thing a cell holds and return TRUE or FALSE.

Before a formula does something with a cell, it sometimes needs to ask what is in it. Is it empty? Is it a real number or text that looks like one? Did the lookup fail? The IS functions answer with TRUE or FALSE, and are nearly always used inside IF.

Syntax

=ISBLANK(value)

=ISNUMBER(value)

=ISTEXT(value)

=ISERROR(value)

=ISNA(value)

Argument	What it is
`value`	The cell or formula to test.

Examples

Each result below is what Excel itself showed for the formula on the sample sheet.

Sample sheet: Marks of eight students in three subjects. One Science mark is missing (cell D6 is empty).

	A	B	C	D	E
1	Name	Class	Maths	Science	English
2	Asha	8A	78	85	91
3	Ravi	8B	45	52	60
4	Meena	8A	92	88	79
5	Kabir	8B	33	41	38
6	Tara	8A	67		72
7	Joy	8B	88	90	84
8	Neha	8A	54	61	58
9	Imran	8B	78	73	69

=ISBLANK(D6)
Result: TRUE
Tara's Science mark is missing. The cell is truly empty: TRUE.
=ISBLANK(D2)
Result: FALSE
A cell with a number in it is not blank.
=ISNUMBER(C2)
Result: TRUE
The mark 78 is a number.
=ISNUMBER(A2)
Result: FALSE
A name is not a number.
=ISTEXT(B2)
Result: TRUE
The class "8A" is text.
=IF(ISBLANK(D6),"Absent",D6)
Result: Absent
The usual pattern: test the cell, then decide what to show.

Sample sheet: Text as people really type it: stray spaces, mixed capitals, codes with dashes.

	A	B	C	D
1	Full name	Email	Code	Amount as text
2	asha verma	asha.verma@example.com	PB-10-1234	1,250
3	RAVI KUMAR	ravi@example.org	DL-08-0042	300
4	meena gill	meena.gill@example.com	MH-12-9876	45.50
5	Kabir Khan	kabir@example.net	RJ-14-0007	12 kg

=ISNUMBER(D3)
Result: FALSE
"300" stored as text looks like a number, but ISNUMBER says FALSE. This is the quickest test for numbers stored as text.
=ISNUMBER(VALUE(D3))
Result: TRUE
After VALUE converts it, the answer is TRUE.
=ISERROR(VALUE(D5))
Result: TRUE
VALUE of "12 kg" is an error, so ISERROR is TRUE.
=ISNUMBER(SEARCH("gill",A4))
Result: TRUE
With SEARCH: does the cell contain this text?

The family

Function	TRUE when the cell holds
ISBLANK	nothing at all
ISNUMBER	a number, a date or a time
ISTEXT	text
ISNONTEXT	anything that is not text, including an empty cell
ISLOGICAL	TRUE or FALSE
ISERROR	any error value
ISNA	the `#N/A` error only
ISERR	any error except `#N/A`
ISFORMULA	a formula
ISEVEN, ISODD	an even or an odd number

ISBLANK and cells that only look empty

ISBLANK is strict. It is TRUE only for a cell with nothing in it. It is FALSE for:

a cell containing a space;
a cell with a formula that returns empty text "", which looks blank on screen.

Because of the second case, many people test with =A2="" instead. That comparison is TRUE both for a truly empty cell and for a formula returning empty text, which is usually what is wanted: "does this cell show nothing?"

ISNUMBER: the test for real numbers

=ISNUMBER(A2) is the quickest way to find numbers stored as text, the hidden cause of totals that will not add up. Put it in a helper column and filter for FALSE. See VALUE for the cure.

It is also the second half of two standard patterns:

Does a cell contain a text? =ISNUMBER(SEARCH("text", A2)). SEARCH returns a position when it finds the text and an error when it does not.
Is a value in a list? =ISNUMBER(MATCH(A2, list, 0)).

Dates are numbers, so ISNUMBER is TRUE for a real date and FALSE for a date typed as text. That makes it a test for bad dates too.

ISERROR, ISNA and IFERROR

Before Excel 2007, errors were handled like this:

=IF(ISERROR(VLOOKUP(...)), "Not found", VLOOKUP(...))

The lookup had to be written twice. IFERROR does the same in one go, and IFNA handles only the "not found" case. The IS versions are still the right tool when you want a TRUE or FALSE, for example to count the errors in a column: =SUMPRODUCT(--ISERROR(A2:A100)), or to use as a Conditional Formatting rule that colours failed lookups.

Prefer ISNA to ISERROR for lookups, for the reason given on the IFERROR page: it reacts to a missing value and does not hide a real mistake in the formula.

In Data Validation and Conditional Formatting

The IS functions make good rules.

Allow only numbers in a column: a custom validation rule of =ISNUMBER(A2).
Allow only text: =ISTEXT(A2).
Shade cells that are still empty in a form: a formatting rule of =ISBLANK(A2).
Shade cells that contain a formula, to tell typed values from calculated ones: =ISFORMULA(A2).

Testing a whole range

Applied to a range, an IS function returns a TRUE or FALSE for each cell. Two minus signs turn those into ones and zeros that can be added: =SUMPRODUCT(--ISTEXT(A2:A100)) counts the text cells. =SUMPRODUCT(--ISNUMBER(A2:A100)) gives the same answer as COUNT.

Common mistakes

Expecting ISBLANK to be TRUE for a cell holding a formula that returns "".
Using ISERROR where ISNA would be safer.
Testing for text numbers with ISTEXT and forgetting that genuine text, such as a note, is TRUE as well.
Forgetting that a date is a number: ISNUMBER on a date cell is TRUE.

In Google Sheets

The same IS functions exist in Google Sheets. Sheets also has ISDATE, ISEMAIL and ISURL, which Excel does not.

Related functions

Every result on this page was calculated in Microsoft Excel (version 16.0, build 20326) on 12 November 2026, not typed by hand.

This is an independent help site. It is not connected with or approved by Microsoft. Excel and Microsoft 365 are trademarks of Microsoft Corporation, named here only to say which program a formula is for. The people and figures in the sample sheets are made up.