How to Shrink Large PDF Attachments That Exceed Email Size Limits

Most email providers cap file attachments at 20–25 MB, and PDFs containing scanned pages or high-resolution images can easily exceed that limit. The right fix depends on the source of the bloat — scanned documents benefit from lower DPI settings (150–200 is typically sufficient), while photo-heavy PDFs should have images compressed before being assembled into the file. For existing oversized PDFs, tools that recompress embedded images or split the document into smaller parts offer practical workarounds. Compressing images to 75–85% quality before building a PDF can reduce file size by 70–90% with little visible difference at normal viewing sizes. Experts advise always retaining the original uncompressed file, since compression permanently discards image detail that cannot be recovered.