PDF Too Big to Email? How to Shrink or Split It

A PDF over an attachment limit can be fixed in two ways: reduce the images inside it, or split it and send the parts separately. This guide lists the steps we actually ran with this site's Compress PDF and Split PDF tools.

Last updated: 2026-10-22

What should I check first?

Compare your PDF's size with the attachment limit of the recipient. Limits differ between email services and submission sites, so take the number from that service's own help page. Knowing how far over the limit you are tells you whether compression is enough or you need to split.

How much does compression save?

Files whose size is mostly photos or scans shrink a lot; files made of text and tables barely shrink. These are results from test PDFs we made ourselves. Your files will differ, so treat them as a rough guide only.

Steps to compress

1. Open Compress PDF and add your PDF (several files are allowed).
2. Choose a compression level. Light favors quality (images up to 2400px on the long side), Medium is up to 1600px, and Strong favors a small file (up to 1100px, lower quality).
3. Click Compress.
4. On the result screen, compare the size before and after, and compare the Original, page 1 and Compressed, page 1 pictures side by side.
5. If the text is still readable, click Download PDF. If it looks blurry, click Try another level and go one step lighter.
6. Check that the new size is under the recipient's limit.

What if it is still too big?

Split the file and send it in several parts. Our 3-page test PDF (5.6 MB) split with Every page in Split PDF came out as 3 PDFs of 1.9 MB each.

1. Add the file to Split PDF.
2. Choose how to split: Page ranges, Every N pages, Every page, or Extract pages.
3. Click Split, then download each file or click Download all as ZIP.
4. Check that each file is under the limit and send them separately.

Splitting copies each page's content from the original, so it does not redraw images or lower their quality. The size that remains is whatever the images on those pages take up.

When this does not work

• Text-and-table PDFs barely shrink (7% for our test file). If you need more room, split the file instead.
• Password-protected PDFs cannot be compressed or split. → Can't Merge or Split a Protected PDF?
• CMYK images and JPEG 2000 images are not reduced.
• Compression saves images again as JPEG, so quality may drop slightly. For files with stamps or signatures, zoom in and check after downloading, and keep the original.

For more on why PDFs are large, see How to reduce PDF file size. If you need to combine files, see How to merge several PDFs into one.

Go to Compress PDF

Last updated: 2026-10-22