Syntax
=ISNUMBER(value)
value- The value or cell to check.
ISNUMBER function in Google Sheets
ISNUMBER returns TRUE if a value is a number. On its own it checks data types, and wrapped around SEARCH it becomes the go-to "does this cell contain…" test.
Practice ISNUMBER
Task 1 of 2
This column was typed by hand and some entries aren't real numbers. Return TRUE in B2 if A2 holds a number.
Tip: while typing a formula, click a cell or drag across cells to insert references. Press Enter to check, and Tab to accept a function suggestion.
ISNUMBER examples
Each example below runs against this sample sheet. The results are calculated by the same engine as the practice grid.
| A | B | C | |
|---|---|---|---|
| 1 | Raw name | SKU | Note |
| 2 | maya PATEL | ELC-0427-NY | Refund requested |
| 3 | leo rossi | FUR-1180-TX | Shipped |
| 4 | AVA KIM | OFC-0093-CA | Refund issued |
| Formula | Result | What it shows |
|---|---|---|
=ISNUMBER(SEARCH("refund", C2)) | TRUE | SEARCH found "refund", so ISNUMBER returns TRUE. |
=ISNUMBER(SEARCH("refund", C3)) | FALSE | Not found: SEARCH errors and ISNUMBER returns FALSE. |
=ISNUMBER(B2) | FALSE | A SKU is text. |
=ISNUMBER(VALUE(MID(B2, 5, 4))) | TRUE | The middle part of the SKU converts cleanly to a number. |
Tips and common mistakes
- Numbers stored as text return FALSE. That makes ISNUMBER a quick way to detect them after an import.
- Dates are numbers in Google Sheets, so ISNUMBER returns TRUE for them.
Related functions
Learning step by step? ISNUMBER is covered in Lesson 10: ISBLANK, ISNUMBER & IS Functions of the free course.