How do XLSX and CSVcompare? Here's everything you need to know to choose the right format — and how to convert between them.
Office Open XML Spreadsheet
XLSX is the default format for Microsoft Excel spreadsheets. It supports complex formulas, charts, pivot tables, and large datasets. It's the industry standard for data analysis and financial modeling.
Comma-Separated Values
CSV is the simplest tabular data format — rows of values separated by commas. It's the universal exchange format for data between databases, spreadsheets, and programming languages.
| Specification | XLSX | CSV |
|---|---|---|
| Full name | Office Open XML Spreadsheet | Comma-Separated Values |
| Extension | .xlsx | .csv |
| MIME type | application/vnd.openxmlformats-officedocument.spreadsheetml.sheet | text/csv |
| Category | Document | Document |
| Developer | Microsoft | IBM (original concept) |
| Year introduced | 2007 | 1972 |
XLSX and CSV serve different purposes. XLSX is ideal for financial reports and budgets, while CSV excels at data import and export.
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