How to compress a pdf file to reduce the size before emailing on Windows?

You can usually reduce a PDF’s size by opening it in Adobe Acrobat and using the “Compress PDF” or “Reduce File Size” option. If you don’t have Acrobat, there are also free PDF compression tools available online that work well for basic files. Another thing that helps is lowering image quality inside the PDF before saving it again, especially if the document contains screenshots or scanned pages.