XLS Converter
Convert files to and from XLS online for free. Fast, secure, and high-quality file conversion with no sign-up or software required.
Maximum file size is 1GB
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Three steps to your converted file
Everything happens in your browser tab - upload, pick a format, download. The heavy lifting runs on our servers.
Upload your file
Drag and drop, click to browse, or paste a URL. Batches take up to 20 files at once - 230+ input formats across video, audio, image, document, and archive types.
Choose an output format
Pick from over a hundred output formats. Filter by category or search by name - every option is open to everyone, no account needed.
Convert & download
Hit Convert and grab your download link moments later. Originals are erased when the job completes; results are cleared within about an hour.
What is an XLS file?
The XLS format utilizes the Binary Interchange File Format (BIFF) scheme, serving as the default spreadsheet standard for Microsoft Excel from versions 2.0 through 2003. Encapsulated within the Object Linking and Embedding (OLE) Compound File Binary Format (CFBF), XLS files store data in binary streams rather than XML. This proprietary structure supports formulas, Visual Basic for Applications (VBA) macros, and charts but lacks the compression efficiency and corruption resilience of the newer XML-based standards.
How to open an XLS file
Microsoft Excel remains the primary software for full fidelity access to XLS files. On Windows and macOS, the operating system associates these files with the Office suite if installed. Alternatively, open-source solutions like LibreOffice Calc and Gnumeric provide robust reverse-engineered support for reading and editing XLS binaries on Linux and other platforms without requiring Microsoft licenses.
XLS Technical Info
- Full Name
- Excel Binary File Format
- Developed By
- Microsoft
- Initial Release
- 1987
- MIME Type
- application/vnd.ms-excel
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