Downsides to Microsoft Excel 2007 XLSB binary format?

Question

Excel 2007/2010 offers an option to save my files in an "Excel Binary Workbook" format that seems to be smaller (50% of the size in some cases) and load more quickly. Is there a downside to this format? Should I be avoiding it for some reason?

I'm thinking there has to be some shortcoming to it, or it would be the default save format instead of XLSX, but I can't figure out what the faults might be. XLSX seems to be reasonably common in other products that can import Excel files, but none of them support XLSB - why not?

Answer 1

As stated, xlsb is a binary file type, and saves in binary format. All other xls file types save in open XML format. We're not here to talk about advantages, but disadvantages.

1. The only real disadvantage is going to be compatibility in using the data with software that wants XML instead of binary (web server for instance). If you link a lot of systems together, this may cause a problem with one of the layers, as XML was developed specifically for this purpose.

2. Overall, there are no other disadvantages other than the fact that you might not be able to tell if there are macros in it or not as there is no macro-free version of this format. You can just change your macro settings to disable with prompt and examine visual basic to determine if there are harmful macros.

A compelling list to use xlsb as your default file format.

Answer 2

I don't use the xlsb format for two reasons.

1. Because the file has all of the XML plus the binary, the file is larger than the corresponding xlsx or xlsm file.

2. When I was working with a large and complex file, the binary would get corrupted frequently and I would have to restore from a back up copy of the file.

Update: I tried the xlsb format when it first came out and had the above problems. Problem 1 doesn't happen with Excel 2010 so maybe problem 2 is fixed also.

On the other hand, even if all of the above is fixed, I still won't use xlsb very often because most of my Excel files are actually VBA projects. Tracking a binary in a code repository will bloat the repository pretty quickly. (I use Mercurial for my code repository and, with the zipdoc extension turned on, I can tell it that xlsx AND xlsm files are zipped XML text files instead of binary.)