Excel IS Functions: Complete Guide to ISNUMBER, ISTEXT, ISBLANK, ISERROR & More (Video in Khmer)

Hello everyone! Today I show you complete guide how to use IS Functions in Microsoft Excel step by step with simple examples, helpful tips, and video tutorials in Khmer.

In Excel, IS Functions is group of logical functions that check cell value or condition. If condition is true, formula return TRUE. If condition is false, formula return FALSE. They are very useful when checking data before running calculations or hiding formula errors!

📊 Quick Summary: Overview of Excel IS Functions

1. How to Use ISNUMBER Function in Excel

ISNUMBER function check if cell contains number value.

⚠️ Note: In Excel, Dates and Times are stored as numbers behind the scene, so ISNUMBER return TRUE for dates too!

Syntax:

=ISNUMBER(value)

Examples:

• =ISNUMBER(100) ➔ TRUE
• =ISNUMBER("Excel") ➔ FALSE
• =ISNUMBER("100") ➔ FALSE (Because "100" inside quote is text format!)

📹 Video Tutorial for ISNUMBER (Khmer):

2. How to Use ISTEXT Function in Excel

ISTEXT function check if value inside cell is text.

Syntax:

=ISTEXT(value)

Examples:

• =ISTEXT("Hello") ➔ TRUE
• =ISTEXT(500) ➔ FALSE
• =ISTEXT("") ➔ TRUE (Empty string from formula is treated as text!)

📹 Video Tutorial for ISTEXT (Khmer):

3. How to Use ISBLANK Function in Excel

ISBLANK function test if cell is completely empty (no numbers, no text, no hidden space, no formula).

Syntax:

=ISBLANK(value)

Examples:

• =ISBLANK(A2) ➔ TRUE (If cell A2 has nothing inside)
• =ISBLANK(A2) ➔ FALSE (If cell A2 has space " " or formula returning "")

📹 Video Tutorial for ISBLANK (Khmer):

4. Other Important IS Functions in Excel

🔴 ISERROR & ISNA Functions

• ISERROR(value): Returns TRUE if cell contain ANY error like #N/A, #VALUE!, #REF!, #DIV/0!, #NAME?, #NUM!.
• ISNA(value): Returns TRUE ONLY if cell error is strictly #N/A (Not Available). Great for checking VLOOKUP or XLOOKUP missing lookup values!

🔢 ISEVEN & ISODD Functions

• ISEVEN(number): Returns TRUE if number is even integer (e.g., 2, 4, 6, 8, 0).
• ISODD(number): Returns TRUE if number is odd integer (e.g., 1, 3, 5, 7).

📝 ISFORMULA Function

• ISFORMULA(reference): Returns TRUE if cell contain formula like =A1+B1 or =SUM(A1:A10). Returns FALSE if cell is plain entered value.

💡 Important Tips & Hints

💡 Tip 1: How to Search Keyword inside Text using ISNUMBER + SEARCH
SEARCH function returns number position if keyword found, but returns #VALUE! error if keyword not found. Combine with ISNUMBER to get clean TRUE/FALSE:
=ISNUMBER(SEARCH("apple", A2))
If cell A2 has "Green Apple Juice", formula returns TRUE!

💡 Tip 2: Watch Out for Empty String "" in ISBLANK
If formula in cell A2 returns "" (empty string), ISBLANK(A2) will return FALSE because cell contain formula!
Better Solution: Use =A2="" or =LEN(A2)=0 to check if cell looks blank.

💡 Tip 3: Combine IS Functions with IF Function
IS functions usually used inside IF function to make smart logical decisions:
=IF(ISNUMBER(A2), A2 * 10%, "Please enter valid number")
If A2 is number, calculate 10%. If user type text, display friendly warning message!

💡 Tip 4: Highlight Formula Cells with ISFORMULA + Conditional Formatting
Want to see which cells in your report have formulas?
Select your data table ➔ Conditional Formatting ➔ New Rule ➔ Use a formula to determine which cells to format:
Formula: =ISFORMULA(A1)
Set fill color to light yellow. Now all formula cells highlight automatically!

💡 Tip 5: Clean Up Old VLOOKUP Errors with ISNA or IFERROR
If VLOOKUP cannot find match, it returns #N/A. You can hide error nicely:
=IF(ISNA(VLOOKUP(A2, C:D, 2, FALSE)), "Not Found", VLOOKUP(A2, C:D, 2, FALSE))
(Note: In modern Excel 2013+, you can also use IFNA(...) or IFERROR(...) for shorter formula!)

📚 Useful Resources

• EXACT vs SEARCH vs FIND Function in Excel (Video in Khmer)
• How to Use Text Cleaning Formulas in Excel (LEFT, RIGHT, MID, LEN, TRIM, CLEAN)
• Top 15 Basic Excel Formulas Every Beginner Should Know