XLSX – Microsoft Excel Workbook
XLSX is the standard Excel format. It stores sheets, formulas, formatting and charts in a zipped XML package.
More XLSX conversionsDrop your XLSX files here
or click to choose XLSX files · up to 95MB each
How to convert XLSX to XLS
- Choose your files. Click Select File or drag your XLSX files into the upload box. You can add many at once.
- Pick the settings. XLS is already selected as the output format. The conversion starts as soon as a file is added.
- Download. Each file appears in the list when it is ready. Download them one by one, or all together with Download all.
Why convert XLSX to XLS?
Some older accounting programs, company systems and Excel 2003 can only open the old XLS format. Converting XLSX to XLS makes your spreadsheet readable in those programs.
When to keep the XLSX
Keep the XLSX as your main file: it supports more rows, columns and functions than the old XLS format can.
Tips for the best result
- XLS holds at most 65,536 rows and 256 columns; data beyond that is cut off.
- All sheets and normal formulas are converted.
- Newer Excel functions may not exist in XLS and can show an error in old Excel.
Common problems and fixes
- Some rows are missing.
- XLS cannot store more than 65,536 rows. Split large sheets before converting.
- A formula shows an error in the old program.
- The function was added in a newer Excel version. Replace it with an older equivalent.
XLS – Microsoft Excel 97-2003 Workbook
XLS is the legacy binary Excel format used before 2007. It is limited to 65,536 rows and is usually converted to XLSX or CSV.
More XLS conversionsConverting XLSX to XLS
- CSV and TSV keep only the first sheet and no formatting.
Frequently asked questions
Why would I need XLS today?
Only for old software or systems that cannot read XLSX. For everything else XLSX is better.
Is conditional formatting kept?
Basic formatting is kept; newer styles may be simplified.
How do I convert XLSX to XLS?
Click Select File or drop your XLSX file onto the upload box. The converted XLS appears in the list below with a download button. You can add many files at once and download them together as a ZIP.
Is it really free?
Yes. There is no sign-up and no watermark. To keep the service available for everyone there is a 95MB limit per file and a cap on how many files one connection can process in a short period.
Are my files stored?
Your upload is used only to make the converted file. Images are processed in memory; other files are written to a private temporary folder that is deleted as soon as the conversion finishes. Nothing is kept after the result has been sent back.
Will quality drop?
For images, a little, by design: the image is re-encoded at the Quality you choose (default 75%). Audio and video are re-encoded with high-quality settings; documents keep their text and layout as far as the target format allows. Converting never restores detail that is already missing from the original.
How this works: your file is uploaded over HTTPS and converted on this server with open-source engines (libvips for images, FFmpeg for audio and video, LibreOffice and Pandoc for documents, Calibre for ebooks, Ghostscript and Inkscape for PDF and vector files). Images are processed in memory; other files use a private temporary folder that is deleted as soon as the conversion finishes.