Direct conversion from PAGES (iWorks Pages) to XLSX (Microsoft Excel) is most likely not possible. However using a copy + paste with both programs opened, it should be possible to copy certain elements out of opened *.pages document and save it as *.xlsx in Excel. That however works only for Mac users, as there is no iWorks for Windows.
Convert Pages document to Microsoft Excel Open XML workbook and spreadsheet.
We found one software available in the database for this conversion.
On-line services software - convert pages to xlsx on web
An on-line version of Pages, Numbers, and Keynote
Convert from pages file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.