How to convert Excel file to CSV format

Although Microsoft Excel allows you to save a file in different formats, it is more convenient to use special tools for this.

There are two programs to convert Excel (xls, xlsx) files to CSV. Both converters can work in two modes:
- a wizard, using graphic interface
- using a command line

In the first case you select one or more XLS or XLSX files, choose the output folder, and set different options to customise the output files.
i.e. you can select a field delimiter: comma, semicilon or TAB. you can conclude values in quotes, etc.

In the second case you use command line interface:
it allows you to run converters with predefined parameters manually or using scheduler to automatise routine work.

For example (Windows and OSX):

xls2csv.exe c:\source\file.xls -output=./target/ -batch -fields=; -quotes=1 /users/owner/file.xls -output=d:\target\ -batch -fields=, -records=CRLF