The essentials
Common sources of size are large bitmaps, repeated graphics, embedded fonts, layers and attached files. Simply opening and saving a document does not guarantee a smaller output; in some cases it increases the file size.
Practical steps
If you are creating a PDF from images, choose source resolution based on your use case. A screen-sharing copy may need less detail than professional print artwork, but avoid making small text unreadable.
What to double-check
SatrPDF does not advertise a fake one-click compression guarantee. Use a tool that describes what it compresses, then compare file size and readability before distributing the result.
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