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What is the real difference between a .xls vs .xlsx file ?

Anonymous
2012-03-20T01:05:13+00:00

Hi ...  Can somebody point me to a credible source of information explaining what are the real differences between a .xls and .xlsx file ?  I have many .xls file.  I began using Office v14 recently and wonder if it is useful to change them all to .xlsx instead of still saving them to .xls format.

What will I be loosing or missing ?

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  1. Anonymous
    2012-03-20T10:28:03+00:00

    Take a look at the "Benefits of the New File Formats" section here:

    http://msdn.microsoft.com/en-us/library/aa338205(v=office.12).aspx

    If none of the benefits are things you're interested in, there's no reason to change.

    In general, .xlsx/.xlsm files are somewhat less likely to become corrupt, and can be smaller, but if you make regular backups and have plenty of disk space, there's no reason to spend the time converting.

    OTOH, there's usually no reason not to take advantage of the OOXML formats for new files that you create.

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  1. Anonymous
    2012-03-20T02:01:46+00:00

    Read the information at this link: http://www.differencebetween.net/technology/difference-between-xls-and-xlsx/

    Although geared to windows version the information appears to apply to the Mac versions as well except for the office package versions  2003 (as opposed to 2004) and so on.

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  1. Jim G 134K Reputation points MVP Volunteer Moderator
    2013-03-22T13:46:07+00:00

    Here's a relevant article that may be of interest

    **Choosing Excel File Formats in Office 2011 for Mac**

    As you said, with old .xls format files the format and file extension is the same regardless of whether or not the file contains macros. Additionally .xls is a binary format file that takes minimal disc space.

    The current file format the works the same way is Excel Binary Workbook .xlsb. This file format supports workbooks with and without macros just like the old format. The new .xlsb format is also binary so it takes minimal disc space.

    You can tell Excel 2011 to always use .xlsb format. Open Excel Preferences and click on Compatibility. Click the popup for Save Files in this Format. Change the setting to Excel Binary Workbook .xlsb and then click the OK button.

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  2. Anonymous
    2012-03-20T14:02:47+00:00

    I can't see much downside, except that .xls files are a bit more prone to corruption than .xlsx/.xlsm files. But "more prone" is a relative term - neither type of file corrupts very often. Just keep regular backups...

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  3. Anonymous
    2012-03-20T13:29:17+00:00

    Thank you Phillip and J.E. ...  

    Reading both articles, it does not seem to concern me at all, neither now nor in a near and far future.  I have mostly small regular .xls files with no macros.  Only 2 or 3 of them have macros.

    You certainly recall the problem I had with a file in a recent thread.  It was a .xls file that contained macros.  I had to delete all those macros to be able to run it using Excel 2011.  I saved it in .xlsm.  Iwas considering to convert all my files to .xlsx and .xlsm format until it occurred that I had also been able to open .xls file with and without macros in Excel 2011 without any problem.

    It seems now obvious that by upgrading to Excel 2011, I had a problem with only one file not all of them.

    I am thinking of keeping all my files in .xls format.  I would recreate the macros that I deleted from my problem file and save it also to .xls.

    Would that be a safe and sound ?

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