Photoshop: What's w/ the 20-30 kb difference between what my save-to-web compression says will be the size of the file & the actual size of the file after saving? Any fix to this, so when compressing I have an accurate idea of my final file size?
That depends on the options you specify. It could be metadata, a color profile, etc.
Or on Macintosh, you could be looking at the combined data + resource size (including resource thumbnails in CS6 or older versions).
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