Please note: xlsReadWrite[Pro] is deprecated.

(A new version, xlsReadWrite v1.5.5, has just been uploaded and now the package supports again the latest R version (tested with R3.0.3 on Windows 8.1. But alas, without crossplatform and xlsx support and only working with the 32-bit R exe, the package just isn't relevant anymore (a successor was planned but didn't materialize for 'some reason' and it's unsure if it ever will).)

xlsReadWrite is an R package which allows to read and write Excel files natively, without any dependencies such as Excel, ODBC drivers, Perl, Python or Java.

Supported is the .xls file format (

Our own code is free (GPL-2) but we also use proprietary code which can only be distributed legally in compiled form and the package contains a binary library. (The CRAN version [edit: cran version is archived now] generates a placeholder dll/so and the regular library must be downloaded with 'xls.getshlib()').
  • System requirements: 32-bit R version.
  • License: the xlsReadWrite package including the pre-compiled dynamic library can be freely distributed and used for any purpose. All components other than xlsReadWrite.dll/so are licensed under GPL version 2 with an explicit exception to allow to link the non-free flexcel code.
  • Requirements to compile for yourself: License for Delphi 2007 and Flexcel.