You hit send and the email bounces: the attachment is too big. Most email services limit attachments to roughly 20 to 25 MB, and a scanned PDF can blow past that. Here is how to shrink one, privately.
Why some PDFs are huge
Text is tiny. Pictures are not. A PDF made from scans, phone photos or a slide deck full of images can run to tens of megabytes, because every page is a large picture. A report that is mostly words is usually small already.
How to compress a PDF in your browser
- 1
Open Compress PDF
It runs on your device, so the file never leaves it.
- 2
Drop your PDF
You will see its current size.
- 3
Start with Recommended
This shrinks the pictures inside the document and leaves text sharp and selectable.
- 4
Download and check
Look at the new size. If it is still too big, run the original again with Strong.
- 5
Use Maximum only if you must
It turns pages into images for the smallest file, but you can no longer select text.
Other ways to get under the limit
- Delete pages you do not need with Organize PDF.
- Send only the part that matters: extract it with Split PDF.
- Split a very large file into two emails.
- Share a link from your cloud drive instead of an attachment.
Check the result before you send
Open the compressed file and zoom in on the smallest text and any important pictures. If something looks too soft, go back to the original and choose a gentler level. Always keep the original, because compression cannot be undone.