📎 This article includes 1 downloadable practice file ↓
In this article
ISFORMULA returns TRUE when a cell contains a formula. Use it in conditional formatting to catch numbers someone typed over a formula column.
Syntax
=ISFORMULA(reference)| Argument | What it means |
|---|---|
reference |
A cell. |
Examples
Example 1
=NOT(ISFORMULA(D2))Conditional-formatting rule: highlight overwritten cells.
ISFORMULA in practice
Where you will use it
- Highlight hard-coded numbers in a model
- Audit inputs vs calculations
- Protect formula cells
Worked example
| Cell | Formula | Result |
|---|---|---|
| 4 | =ISFORMULA(A2) | TRUE |
| 4 | =ISFORMULA(A3) | FALSE |
| 04-10-2026 | =ISFORMULA(A4) | TRUE |
Results calculated in Excel.
Mistakes people make
| Mistake | What to do instead |
|---|---|
| Constant typed over a formula | Conditional-format with ISFORMULA to catch it |
| Range input | Point to one cell |
Related functions
📚 Part of the free Excel course: Beginner → Expert · Try it in the Formula Lab or ask the AI Helper.
⚡ Interactive Practice Lab & Formula Tester:
Test formulas dynamically in our web formula laboratory or download the companion Excel workbook.
📎 Practice files for this article
- 📗Practice workbook: Information (IS…) functions15 tasks on realistic sales data — type your formula, the Check column turns green when it is right. Answers sheet included.⬇ XLSX · 34 KB
Free to use for learning. Files with macros (.bas) are plain text — import them with Alt+F11 → File → Import File, and always test on a copy.
✨ Ask AI about this article
Stuck on a step? Ask a question and the AI answers using this article.
Free · AI can be wrong