00data

XLS

Legacy Excel Workbook (BIFF8)

XLS is the binary Excel format used up to Office 2003. It is capped at 65,536 rows and 256 columns, and modern Excel opens it only in compatibility mode — so most XLS files people hold today are exports from old line-of-business systems that were never updated.

Extension: .xls
MIME type: application/vnd.ms-excel

01 Convert XLS to something else

XLS to CSV The legacy binary Excel format, read in the browser.
XLS to PDF The 1997 workbook format, read here and put on a page.

02 Convert something else to XLS

CSV to XLS The legacy binary format, for systems that will not take XLSX.

03 Related formats

JSON
CSV
TSV
XML
YAML
TOML
XLSX

Opening a .xls file

If you landed here because something handed you a .xls file and nothing on your machine will open it, converting it to a format you already have a reader for is usually faster than installing new software. Every conversion above runs in this browser — the file is not uploaded, so it works on a locked-down work machine and on a file you are not allowed to send anywhere.