What's the maximum PDF size I can email?

Most providers cap attachments around 25 MB (Gmail and Outlook included), and some corporate servers are stricter at 10 MB. Compressing a PDF or splitting it are the two reliable ways under the limit.

Why is my PDF so large?

High-resolution images and scanned pages are the usual cause — a scan stores each page as a full photo. Embedded fonts and duplicated images add to it. Text itself is tiny; images dominate the size.

Does compressing a PDF hurt quality?

Moderate compression is visually lossless for most documents. Text stays sharp because it's stored as vectors; only images are re-encoded, so image-heavy files see the biggest savings and the only noticeable change.

PDF Too Big to Email? How to Shrink It Fast

Short answer: Compress the PDF with the Compress PDF tool — most files drop 40–70% and slip under the 25 MB email limit. If it's still too big, split it into parts and send them separately.

Almost every email provider caps attachments around 25 MB, and stricter corporate systems stop at 10 MB. A single scanned contract can blow past both. Here's why, and how to fix it in seconds.

Why PDFs get so big

Cause	Effect on size
Scanned pages	Huge — each page is a full-resolution photo
High-res embedded images	Large — often the biggest contributor
Duplicated images / logos	Adds up across many pages
Text and vectors	Tiny — rarely the problem

The pattern is simple: images make PDFs big, text doesn't. That's why scans and image-rich brochures are the usual offenders.

The fastest fix: compress

Run the file through Compress PDF. It re-encodes images at an efficient size and strips redundant data, typically cutting 40–70% with no visible change to text. For most email problems, one pass is enough. See our full guide to compressing a PDF.

Still too big? Split it

If a giant scan won't fit even after compressing, split the PDF into two or three smaller files and send them across separate emails — or share a link instead of attaching.

Before you do, check whether the file is carrying pages nobody asked for. Scanners routinely add blank backs and duplicate sheets, and deleting those pages removes their weight outright — a cheaper win than any compression setting.

Prevent oversized PDFs

Scan at 150–200 DPI, not 600 — plenty for documents, far smaller files. This is the single biggest lever on a scan's size, and it has to be pulled before the scan: we measured 24 documents and scanned files compressed by a median of only 2% afterwards.
Compress before sending, especially anything with scans or photos.
Export, don't screenshot — a screenshot of a page is a heavy image; export to PDF from the source instead.

Quick checklist

Compress the PDF.
Under the limit? Send it.
Still too big? Split into parts or share a link.