ISODD function
ISODD returns TRUE when a number is odd. Use it to split items into two groups, alternate seating or batches, or shade odd rows. Negative numbers work, and decimals are dropped first, so 7.5 counts as 7.
- Available in
- Every current version
- Category
- Information functions
- Returns
- TRUE if the number is odd, FALSE if it is even. #VALUE! for text.
- Google Sheets
- Available in Google Sheets with the same argument.
Syntax
=ISODD(number)
| Argument | Required? | What it is |
|---|---|---|
number | Required | The number to test. Decimals are truncated, so 7.5 counts as 7. |
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 |
|---|---|---|---|
| D2 | =IF(ISODD(B2),"Left side","Right side") | Left side | Seat 11 is odd, so it's on the left |
| E2 | =SUMPRODUCT(--(MOD(B2:B6,2)=1)) | 3 | ISODD takes one value at a time, so count a range with MOD |
| F2 | =ISODD(-3) | TRUE | Negative numbers work too |
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
| Ticket | Seat | Row 2 side | Odd seats | Is -3 odd? | |
| T-881 | 11 | Left side | 3 | TRUE | |
| T-882 | 14 | ||||
| T-883 | 23 | ||||
| T-884 | 30 | ||||
| T-885 | 37 |
Practice ISODD
Graded instantly, then re-checked on changed data.
Two teams
In
C2, return Team A when the badge number in B2 is odd, otherwise Team B. Fill down to C8.Common mistakes
| What you see | Why, and how to fix it |
|---|---|
| #VALUE! | The value is text, such as "Seat 11". Extract the number first, for example with VALUE(MID(A2,6,3)). |
| #VALUE! for a whole range | ISODD tests one value at a time. Count odd numbers in a range with =SUMPRODUCT(--(MOD(B2:B6,2)=1)). |
| Decimals give surprising results | 7.5 counts as 7, which is odd, because the decimal part is dropped. Round first if that matters. |
Tips
- Highlight odd rows with the conditional formatting rule =ISODD(ROW()).
Questions
How do I check if a number is odd in Excel?
=ISODD(A2) returns TRUE for odd numbers. =MOD(A2,2)=1 does the same for whole numbers.
Does ISODD work with negative numbers?
Yes. =ISODD(-3) is TRUE and =ISODD(-4) is FALSE.
Last reviewed October 2026. Every example result on this page is calculated live by the Spreadsheet Practice formula engine.