Back up files size change

[Peter Franks]

Any idea when I have a folder on the MBP that says its 421MB and when I save it on an external hard drive it shows 472MB? Makes no sense at all

 

[robbieduncan]

Are both drives using the same format (e.g. HFS+)?

 

[chown33]

What are the capacities of the two drives? Is the external much larger than the other one?

Does the copied folder contain a large number of small files?

 

[belvdr]

Differences in the cluster size of the filesystems is likely the culprit.

 

[Peter Franks]

thanks for replies, It's a Freecom 320GB external and MBP is 320. It doesn't happen on all, but enough, I wonder if ones' missing something or other. Format wise, don't know. Just a drag and drop is my expertise!

 

[Peter Franks]

Yes,... folder does contain a large number of small-ish files