How to see what makes up the file size in a .blend file?

I have a .blend file that’s just an imported .fbx which was 391mb large, and very little added in Blender but now the .blend file is 1.13gb!

How can I find out why it blew up the file size like that?

Whats the poly count? Does it have modifiers like heavy subdivisions and bevels? Does it have complex shading setups? Volumes? Hair?

When I say “very little” I mean I literally just added two array + screw + curve objects to the imported file, a lineart modifer and some simple colored materials, nothing else.

size of objects for array ?
same for the screw ?

can you show edit mode verts in viewport and # of verts ?

imports sometimes have a lot of verts or points !

happy bl

I could be wrong but I do not think that modifiers will blow up file size much as long as they are not applied (at least file size in disk they will blow up memory use when the file is open).

That said a blend file does contain much more information than an fbx file (which I think is also compressed).
You can compress your blend file as well when you “save as”, hit the cog like icon in the save as pop-up widow and click compress. Your file will drastically reduce size, no information should be lost. (In my opinion the compress option could be the default setting)

How big is a file when you import the fbx freshly and save it without any additions?

If you do this and then save as using the compress option how does it compare to the fbx?