Convert XLSX files online for free
The converter easily converts your XLSX file to various formats - free and online. No Excel or extra software needed.
The converter also works in reverse, so you can convert other Spreadsheet formats to XLSX with high quality output.
The .XLSX file is the standard Office Open XML spreadsheet format introduced by Microsoft with Office 2007. Unlike the older binary XLS, this format stores data in a compressed ZIP archive containing XML text files, making it lighter and more robust against corruption. While it is the industry standard for financial models, data analysis, and tabular records, it often creates friction for users without a paid subscription to Microsoft Excel. Viewing these files on mobile devices can be cumbersome, and complex formatting often breaks when opened in non-Microsoft alternatives like Google Sheets or LibreOffice Calc. Furthermore, .XLSX files cannot execute macros (which requires XLSM), but they can still pose security risks if they contain malicious external links.
To overcome compatibility hurdles or software costs, converting your spreadsheet is often necessary. For professional reporting and archiving where layout must remain static, converting to PDF is the best choice. If you need to import the raw data into a database or use it programmatically, converting to CSV (Comma Separated Values) removes all formatting overhead. For legacy systems that strictly require the pre-2007 format, you can revert files to XLS. You can also make spreadsheets web-ready by converting them to HTML or JSON. convert.guru allows you to instantly view and transform your Excel workbooks without installing heavy office suites.
Use Convert.Guru to open and convert your XLSX file.
Users also converted CSV, PDF, WORKSHEET, SAV, GEDCOM, ANKI, PBIX, EXE, XL, IIF, WORKBOOK, XBRL and XLS files.
The history of Convert.Guru began over 25 years ago in California with Tom Simondi’s file-format database. A former contributor to Space Shuttle development and a software pioneer of the 1980s, Simondi established a trusted resource for file type analysis that was even referenced by Microsoft Windows XP. Today, we use modern technology to process and convert thousands of file formats while continually improving our XLSX converter.