ISNUMBER function
ISNUMBER returns TRUE when a value is a real number, which includes dates and times. Its two everyday jobs: spotting digits that were imported as text, which SUM silently skips, and turning SEARCH into a yes-or-no "contains" test.
- Available in
- Every current version
- Category
- Information functions
- Returns
- TRUE if the value is a number (dates count), FALSE for text, blanks, logical values and errors.
- Google Sheets
- Available in Google Sheets with the same argument.
Syntax
=ISNUMBER(value)
| Argument | Required? | What it is |
|---|---|---|
value | Required | The value or 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 |
|---|---|---|---|
| C2 | =ISNUMBER(B3) | FALSE | FALSE: the 8 was imported as text |
| D2 | =SUMPRODUCT(--ISNUMBER(B2:B5)) | 2 | Only two quantities are real numbers |
| E2 | =IF(ISNUMBER(SEARCH("ink",A4)),"Yes","No") | Yes | SEARCH finds "ink", so ISNUMBER is TRUE |
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
| Item | Qty | Row 3 is a number? | Real numbers | Row 4 mentions ink? |
| Pens | 12 | FALSE | 2 | Yes |
| Paper | 8 | |||
| Ink cartridges | 5 | |||
| Tape | n/a |
Practice ISNUMBER
Graded instantly, then re-checked on changed data.
Totals only for real quantities
D2, return quantity times price when the quantity in B2 is a number; otherwise return Check qty. Fill down to D7.Common mistakes
| What you see | Why, and how to fix it |
|---|---|
| FALSE for a number you can see | The number is stored as text, often from an import; look for left alignment or a green triangle. Convert it with VALUE(B2) or Data > Text to Columns. |
| FALSE for a date | The date was typed or imported as text, such as "3/5/2026" from a CSV. DATEVALUE converts it to a real date. |
| A contains test that shows #VALUE! | SEARCH and FIND return #VALUE! when the text isn't found. Wrap them in ISNUMBER to get FALSE instead. |
Tips
- Count cells that contain a word: =SUMPRODUCT(--ISNUMBER(SEARCH("ink",A2:A50))).
Questions
How do I check if a cell contains a number?
=ISNUMBER(A2). Text that includes digits, such as "Order 42", returns FALSE because the cell is text.
How do I check if a cell contains certain text?
=ISNUMBER(SEARCH("ink",A2)) is TRUE when "ink" appears anywhere in A2. Use FIND instead of SEARCH for a case-sensitive test.
Why does SUM ignore some of my numbers?
They are stored as text. =ISNUMBER(B2) returns FALSE for them; convert them with VALUE or Text to Columns.
Last reviewed October 2026. Every example result on this page is calculated live by the Spreadsheet Practice formula engine.