What is an XLSX file?
XLSX stands for Excel workbook. It was created by Microsoft and first released in 2007. XLSX has been the default Excel format since Office 2007. Inside it is a ZIP archive of XML files, one per sheet, plus styles and shared text.
| Type | spreadsheet |
|---|---|
| Compression | Lossless |
| In a browser | opens in Excel, Google Sheets, Numbers and LibreOffice Calc |
| Common uses | business spreadsheets, reports and anything shared with Excel users |
| MIME type | application/vnd.openxmlformats-officedocument.spreadsheetml.sheet |
Which format should you convert XLSX to?
- XLSX to CSV to import into a database, CRM or email tool.
- XLSX to ODS for LibreOffice and open-standard requirements.
- XLSX to XLS for older software that only reads Excel 97 to 2003 files.
How to open an XLSX file
Whether an XLSX file opens with a double click depends on the device. Here is what works on each, without buying software:
| Windows | Excel opens it on Windows; Google Sheets and LibreOffice Calc are free alternatives. |
|---|---|
| Mac | Numbers opens it, as do Excel for Mac and LibreOffice Calc. |
| iPhone and iPad | Numbers, Google Sheets and the Excel app open it from the Files app. |
| Android | Google Sheets and the Excel app open it from Files by Google. |
| Web browser | XLSX opens in Excel, Google Sheets, Numbers and LibreOffice Calc. |
Want the technical details? See what a .xlsx file is, with its MIME type, file signature and a viewer.
XLSX compared with other spreadsheet formats
How XLSX stacks up against the formats people most often convert it to or from:
| Format | Compression | Usually contains | Released | Best for |
|---|---|---|---|---|
| XLSX | Lossless | several sheets with values, formulas, formatting and charts | 2007 | business spreadsheets, reports and anything shared with Excel users |
| CSV | Lossless | one table of plain text values, one row per line | 1972 | data exports, imports into databases and exchanging tables between programs |
| XLS | Lossless | several sheets with values, formulas and formatting in a binary file | 1997 | older Excel files and systems that still export the legacy format |
| ODS | Lossless | several sheets with values, formulas and formatting | 2005 | LibreOffice and OpenOffice users and public-sector documents |
How to use the XLSX converter
- Choose the format you want in the Convert to menu.
- Drop your XLSX files on the box, or press Choose XLSX files. Several files can go in at once.
- Adjust the settings if you need to; the defaults suit most people.
- Press Convert and save each file with its Download button. Converting to HTML, JPG, PDF, PNG, SVG uses our server, which deletes the file right after; the rest never leave your device.
Tips for converting XLSX files without losing anything
Converting an XLSX file keeps every value exactly; what can change is structure, such as extra sheets, formulas and styling, depending on the target.
- Keep workbooks as XLSX or ODS while you work on them, and export CSV only for importing into other systems.
- CSV keeps one sheet and no formulas; converting back will not restore what was dropped.
- Save CSV files as UTF-8 so names with accents and other alphabets survive the trip between programs.
- Before converting a large workbook, remove unused sheets and ranges to keep the result small.
- Name the header row clearly before exporting CSV; most import tools map columns by these names.
- If numbers with leading zeros, such as postcodes or phone numbers, must survive, format those columns as text before converting.
- When a system rejects your file, check whether it expects a comma or a semicolon as the separator; many European systems use semicolons.
Convert XLSX files from the command line
LibreOffice converts spreadsheets from the command line without opening a window:
soffice --headless --convert-to csv input.xlsxThe converter on this page does the same job in your browser, without installing anything.
XLSX converter FAQ
What is an XLSX file?
XLSX stands for Excel workbook, a spreadsheet format created by Microsoft in 2007. XLSX has been the default Excel format since Office 2007. Inside it is a ZIP archive of XML files, one per sheet, plus styles and shared text.
How do I open an XLSX file?
XLSX opens in Excel, Google Sheets, Numbers and LibreOffice Calc. If the program you need will not open it, convert it to a more widely supported format above.
What is the most common XLSX conversion?
XLSX to CSV is the conversion people search for most. CSV holds a single table of plain text, so the first sheet of the XLSX is saved. Formulas become their last calculated values, and other sheets, formatting and charts are left out.
Does converting XLSX files here upload them?
Only for some conversions. Converting to HTML, JPG, PDF, PNG, SVG uses our conversion server, where the file is deleted as soon as the result is sent back; the other conversions run inside your browser and never leave your device.
Is the XLSX converter free?
Yes. There is no sign-up and no watermark. Conversions that use our server accept files up to 25 MB, with a fair-use limit per hour. The site is supported by advertising.
Can I convert XLSX files on iPhone or Android?
Yes. Open this page in Safari on iPhone and iPad, or in Chrome on Android, choose your XLSX files and download the results to your Downloads folder.
Can I convert several XLSX files at once?
Yes. Drop as many as you like; they are converted one after another, each with its own download button.