Though this was interesting...
Reducing Bloated Illustrator Files
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Each new version of Adobe Illustrator adds at least a few new palettes,
each with its own presets to get you started, like the ones in Graphic Styles,
Symbols and Brushes. Unless you explicitly delete those presets before you save
your Illustrator file, the default options come along for the ride, increasing
file sizes and leading to the malady known as Illustrator Bloat.
Illustrator Bloat can get in the way when you're emailing files, when you're
running out of hard drive space, when you're creating hundreds of small Illy
files for inclusion in a layout program or as web graphics.
It wasn't always this way. I remember I once designed a tabloid-sized, CMYK
magazine cover in Illustrator v6 and the final .eps file was 92K. And then
I put it on a floppy and walked ten miles through a blizzard to deliver it
to the client, because that's what we did before e-mail, dadgumit.
As a comparative test, try this: Open a recent version of Illustrator and
create a new letter-size CMYK document. Drag out a plain old rectangle somewhere
on the page using the default settings (1 pt. black stroke, white fill). Save
the file in native .ai format using the default settings as well.
On my Mac running OS X, creating this with Illustrator CS (the latest version)
results in a file that's 468K. For a rectangle!
Turning off PDF Compatibility in the Save dialog doesn't help, in fact, it increases the file size, even if you keep "Use Compression" turned on. (My rectangle grew to 536K when I tried it.)
To slim down your files, you could tediously go through every palette menu, choose Select
Unused, and click the trash can icon to delete them.
Or if you have Illustrator CS, you could run a built-in Action meant for just this task:
1. With your bloated file open, open the Actions palette (from the Window menu).
2. Select the tenth one down, Delete Unused Palette Items, and Play it.
3. If you've already saved the file, do a Save As and overwrite the previous file.
Running this action and overwriting the file reduced my original rectangle.ai file from
436K to a far more palatable 120K.
Woo-hoo!
Thanks for this tip MORDY G. of designResponsibly.com !!