Why is the size of the same PSD file open on different computers very different?

[XE1379]

I open the computer displays the document occupies only 1GB, open a document in someone else's computer display 7GB and running difficult.

[Akash Sharma]

Hi there, 

It's quite strange that Photoshop will show the file size 1 GB and size on disk is 7 GB on a different computer. 

Which version of Photoshop are you using and on which operating system?

Would you mind sharing a screenshot illustrating the issue? Also, does this only happens with a particular file? If so,  where are you saving this file and how are you transferring it to a different computer?

Thanks,

Akash

[XE1379]

 PSCC2017 WIN10
Are the same version and file

[c.pfaffenbichler]

Which display are you talking about exactly? 

What are the performace preferences? 

Is there any chance that there might be two different versions of the file? 

[XE1379]

 PSCC2017 WIN10

Are the same version and file

[c.pfaffenbichler]

Please post the requested screenshots. 

[c.pfaffenbichler]

And again: Which display are you talking about exactly? 

The information the OS provides or Photoshop’s »Cocument Sizes«? 

[rob day]

If you select Document Sizes from the lower left corner of the file are you seeing a difference in the listed sizes? The first size is the flattened pixels, followed by the size including layers and pixels outside of the canvas.