Most email providers cap attachments — Gmail and Outlook at around 25 MB, others lower — and a scanned or image-heavy PDF can blow past that easily. Here's how to reduce a PDF so it sends without bouncing.
Why PDFs get too big for email
A PDF made from photos or high-resolution scans is essentially a stack of images, which are heavy. Add a few colour pages and you're quickly over the limit. Compressing re-encodes those page images at a lower but still readable quality, often cutting the size by 70–90%.
Compress the PDF
Open Compress PDF, drop in your file, and download the smaller version — or aim for a specific target like 2 MB or 1 MB to be safely under any email limit. Everything runs in your browser, so your document is never uploaded.
Still too big? Split or send a link
If a single PDF won't compress enough, split it into parts and send them across a couple of emails, or remove pages you don't need first. For very large files, a cloud-storage link (Drive, Dropbox) is often more reliable than an attachment. Tip: name the file clearly so the recipient knows what it is.
Keep it readable
The goal is small and legible. The compressor keeps the highest quality that fits, so text and stamps stay clear. If you're starting from a scan, scanning in greyscale rather than full colour produces a much smaller file to begin with.