COLUMNNUMBER Function (Gnumeric)
Convert an Excel-style column label such as AA into a column index using Gnumeric COLUMNNUMBER.
Reference checked: Examples have not been run in this spreadsheet application. How we verify guides
The COLUMNNUMBER function in Gnumeric is used for this task: The Gnumeric manual specifies column labels as text, such as “IV”.
This guide explains how to read the formula, reproduce a concrete example, interpret its result and recognize common input mistakes.
Syntax and arguments
COLUMNNUMBER(name)
Gnumeric formulas normally use commas (,) between arguments. These examples are written for Gnumeric rather than copied unchanged from LibreOffice Calc.
Worked example
=COLUMNNUMBER("AA")
Expected result: 27.
Why it works: Converts the spreadsheet column label AA to its numeric index.
Another practical example
Practice inputs: The argument is the text AB.
=COLUMNNUMBER("AB")
Expected result: 28.
Gnumeric counts A as 1, Z as 26, AA as 27 and AB as 28.
What to watch for
Pass the column letters as text. An invalid column label produces an error.
For LibreOffice Calc formulas, separators are commonly semicolons; the Gnumeric examples here use commas. The arithmetic or official reference supplies the expected result, but Gnumeric has not been executed for this review.
How to use it in your own spreadsheet
- Identify the cells or inputs that correspond to the sample values above.
- Enter the formula in an empty cell, changing the references or literal values to match your sheet.
- Compare the output with a manual check on a small known example.
- Extend the formula to a larger dataset only after you understand the result.
Common problems and practical checks
- Use the correct lookup column or return range, and use exact-match options where appropriate.
- Check for duplicate keys, leading spaces and numbers stored as text in lookup data.
- A pasted formula may produce an error when it uses the other program’s argument separator or unsupported options.
Related functions
Documentation and verification
- Gnumeric official function reference
- Gnumeric function catalog
- Formula and intended behavior were checked against the Gnumeric official function reference; Gnumeric itself was not run in this environment.