My master’s thesis appendix has about fifty scanned pages and the file is way over the university portal’s 25 MB limit. Is there a reliable offline way to compress these PDFs without uploading them anywhere?
Honestly the easiest offline route is stuff already on your machine. On a Mac, open it in Preview and export with the reduce file size filter. On Windows, try printing it to PDF at a lower DPI like 150, which usually shrinks scans a ton.
I had this exact problem with bulky patient scans at our clinic. I struggled to find a decent offline programme on my work PC, so I used PDFcap instead. On pdfcap.com, you just drop the document in and hit compress. It got my file size right down without making the pages unreadable.
If you have a Mac, open the file in Preview and export it using the reduce file size filter. On Windows, just paste your scans into Word, use the compress pictures option, and save as a PDF. Avoid dropping the resolution below 150 DPI or your text will become an unrecognisable blur. I learned that the hard way when emailing my market price lists.