getColumnLetterByIndex

function getColumnLetterByIndex(columnIndex: number): string;

Indices count from zero, the way a GridRange does; positions count from one, the way getRange(row, column) does. Mixing the two is the usual source of an off-by-one in a spreadsheet script, which is why both pairs exist under separate names.

Parameters

Parameter	Type	Description
`columnIndex`	`number`	The zero-based column index (e.g., `0` for 'A').

Returns

string — the column letter.

Examples

Converting

getColumnLetterByIndex(0); // => "A"
getColumnLetterByIndex(26); // => "AA"

Source

src/appsscript/sheet/getColumnLetterByIndex.ts

23 September 2026

This documentation was generated with AI (Claude) from the library's source code.

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