Column
AB
Index
28
Encoding & Decoding
Excel Column Letter and Index Converter
Convert between Excel-style column letters (A, Z, AA) and 1-based column indexes. Useful when mapping spreadsheet headers to array indexes in scripts.
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Quick switch:Roman Numeral Converter
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Excel Column Converter
A, B, Z, AA, ...
↔ Bi-directional
Sync
Sync
1, 2, 26, 27, ...
状态：等待输入
Excel 列序号按 1 基计算：A=1，Z=26，AA=27。粘贴 A1 这类单元格引用时会自动提取列名。
Use cases
- Map column letters to indexes in spreadsheet automation scripts
How to use
- Enter a column letter or a 1-based index
- Read the converted value on the other side
- Copy the result
Example input and output
FAQ
Is there an upper limit?
Conversion works within JavaScript safe integer limits for practical spreadsheet column sizes.
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