ISBLANK function
ISBLANK returns TRUE when a cell is completely empty. Use it inside IF to flag missing owners, dates or amounts before they quietly turn into zeros in your totals. It is strict: a cell holding a formula that returns "" is not blank.
- Available in
- Every current version
- Category
- Information functions
- Returns
- TRUE if the cell is empty, FALSE otherwise.
- Google Sheets
- Available in Google Sheets with the same argument.
Syntax
=ISBLANK(value)
| Argument | Required? | What it is |
|---|---|---|
value | Required | The cell to test. |
Examples
Each result below is calculated from the sample sheet by our formula engine, the same one that grades the practice.
| Cell | Formula | Result | What it shows |
|---|---|---|---|
| E2 | =IF(ISBLANK(B3),"Needs owner","Assigned") | Needs owner | Book venue has no owner yet |
| F2 | =SUMPRODUCT(--ISBLANK(B2:B5)) | 2 | Counts the empty owner cells |
| G2 | =IF(OR(ISBLANK(B4),ISBLANK(C4)),"Incomplete","Complete") | Incomplete | Send invites is missing a due date |
Try it live
This is the sample sheet. Change any number or text, or edit a formula, and the results update.
Show the sample data as a table
| Task | Owner | Due | Row 3 owner | Tasks with no owner | Row 4 check | |
| Draft budget | Ana | 3/2/2026 | Needs owner | 2 | Incomplete | |
| Book venue | 3/5/2026 | |||||
| Send invites | Lee | |||||
| Order catering | 3/9/2026 |
Practice ISBLANK
Graded instantly, then re-checked on changed data.
Flag missing emails
D2, return Missing if the email in C2 is empty, otherwise OK. Fill down to D7.Common mistakes
| What you see | Why, and how to fix it |
|---|---|
| FALSE for a cell that looks empty | The cell holds a formula that returns "" or a stray space. ISBLANK is only TRUE for truly empty cells. Test =B2="" instead, or =LEN(TRIM(B2))=0 to catch spaces too. |
| A list of TRUE and FALSE instead of a count | =ISBLANK(B2:B50) tests each cell. To count, use COUNTBLANK(B2:B50) or SUMPRODUCT(--ISBLANK(B2:B50)). |
Tips
- Use it in conditional formatting, =ISBLANK($B2), to highlight every row with a missing owner.
Questions
How do I check if a cell is empty in Excel?
=ISBLANK(A2) is TRUE for an empty cell. =A2="" is TRUE for empty cells and for formulas that return "", which is often what you actually want.
What is the difference between ISBLANK and COUNTBLANK?
ISBLANK tests one value and is FALSE for formulas that return "". COUNTBLANK counts cells in a range and counts those "" cells as blank.
Last reviewed October 2026. Every example result on this page is calculated live by the Spreadsheet Practice formula engine.