Formula Guide

The Excel ISBLANK Function
explained simply

ISBLANK checks whether a cell is genuinely empty, returning TRUE only if there is truly nothing in it.

ExcelPro · 3 min read · Updated June 2026
Contents
  1. What does ISBLANK do?
  2. Syntax
  3. 3 examples
  4. Common mistakes
  5. FAQ

What does ISBLANK do?

ISBLANK returns TRUE if a cell is completely empty, and FALSE if it contains anything at all — including a space, a zero, or an empty-looking formula result.

This distinction matters because a cell that "looks" empty (like one containing a formula that returns "") is not actually blank as far as ISBLANK is concerned.

Syntax

=ISBLANK(value)
ArgumentDescription
value requiredThe cell to test.

Examples

Example 1
Check a genuinely empty cell
=ISBLANK(A2)

Returns TRUE only if A2 has never had anything typed into it.

Example 2
A cell with a formula returning "" is NOT blank
=ISBLANK(A2)

If A2 contains the formula =IF(B2="","",B2), ISBLANK returns FALSE even when it displays nothing — the cell contains a formula, not true emptiness.

Example 3
Flag missing required fields
=IF(ISBLANK(A2),"Missing","Complete")

Useful for data validation, flagging rows where a required field was never filled in.

Common mistakes

⚠️ Confusing a visually empty cell with a truly blank one

A formula result of "" looks empty but is not — use =A2="" instead if you want to catch both true blanks and empty-string results.

FAQ

What is the difference between ISBLANK(A2) and A2=""?
ISBLANK only returns TRUE for genuinely empty cells. A2="" also returns TRUE for cells containing an empty text string, like a formula result of "".

Practise ISBLANK with real data

ExcelPro has hands-on ISBLANK exercises built into real job scenarios — free to start.

Try ISBLANK exercises →

Related formulas

ISNUMBER ISTEXT ISERROR