Your PDF is too large to email

Step by step

1. 1Open Compress PDF and drop the file in — it is read in your browser, not uploaded.
2. 2Try Keep text first: it rebuilds the file and strips metadata while leaving text and vectors untouched.
3. 3If that is not enough, switch to Target size, enter the limit you need (20 MB is a safe stand-in for a 25 MB cap) and let the passes run.
4. 4Check the resulting size and open the download to confirm the pages are still readable.
5. 5If the target could not be met, split the document into parts with Split PDF and send them separately, or share a link instead of an attachment.

What is making the file big

Scanned pages are the usual culprit. A scanner that saves at 600 DPI in colour produces roughly 25 MB per hundred pages even for plain black text, because every page is stored as a photograph of paper rather than as characters. Dropping those pages to 150 DPI is visually almost identical on screen and often cuts the file by 80 percent or more.

Embedded images are next. A phone photo pasted into a document arrives at full sensor resolution — twelve megapixels of detail rendered into a space the size of a postcard. The PDF keeps every one of those pixels even though nothing will ever display them.

Fonts and forms matter less but add up. A document that embeds several full font families, or one built from a form template with hidden layers and attachments, carries weight that is invisible on the page.

Compress first, split second

Start with the Keep text mode of the compress tool. It rewrites the file structure using object streams and drops metadata, and because it never rasterizes anything, your text stays selectable and your vector graphics stay sharp. On a text-heavy PDF this can take a surprising amount off with no visible change at all.

When the file is mostly scans, Keep text will barely move the number, and that is the moment for Target size. Enter the size you need and the tool works down through render settings — 150 DPI, then 120, then 100 and lower — stopping at the first one that fits. If your target would require going below 50 DPI, you get the smallest still-legible version plus a plain statement that the number was not reachable, rather than a blurred file pretending to be a success.

If even that is not enough, the honest answer is that the document is too dense for the limit, and splitting is better than degrading. A contract sent as three readable parts is more useful to the recipient than one unreadable attachment.

When not to attach at all

Some documents should not be email attachments regardless of size. Anything containing bank details, health information or identity numbers sits in the recipient’s mailbox indefinitely and in yours as well. For those, strip the metadata, redact what does not need to travel, and encrypt the file with a password you share over a different channel — a phone call, not the same email thread.

Tools used here

• Compress PDFShrink PDFs locally — keep selectable text by default, or max-shrink with a searchable overlay.
• Split PDFExtract a page range or split into individual pages. Free, private, no upload.
• Delete pagesRemove specific pages by number. The rest stays untouched.
• Remove metadataClear common Info fields (title, author, subject, keywords, dates). Does not scrub every hidden stream.
• Encrypt PDFPassword-protect a PDF so it cannot be opened without the password.