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How to send a PDF under 10 MB or 5 MB

Published 2026-08-31 · Tutorial

Your email service refuses the attachment: over 25 MB, over 10 MB, sometimes just over 5 MB. Here is how to shrink any PDF under the limit in a few minutes, checking the real size as you go, without installing anything.

Know the size your service allows

Gmail allows attachments up to 25 MB, Outlook for the web around 20 MB, while many business portals and application forms cap files at 10 MB or even 5 MB. Before you compress, check what your recipient actually accepts, so you target the right number instead of guessing.

Why the PDF is heavy in the first place

Most PDF weight comes from images: high-resolution photos and scanned pages are the usual culprits, not the text. A multi-page scanned document can reach tens of megabytes while holding almost no readable text. Understanding that tells you that reducing the images is what will actually shrink the file.

Compress to the target in one pass

Open compress a PDF, drop your file and pick a mode. Normal compression keeps the text selectable and typically cuts 15 to 30%, which is often enough to slip under a 10 MB limit. For a scan or a heavy photo pack, maximum compression re-encodes every page as a compact image and can shrink the file dramatically.

Check the real number, then loop

After each pass, look at the actual file size rather than guessing. If you are still over 5 MB, run a second compression or trim the document first. Cut pages you do not need with Remove pages or split the file into smaller parts with Split PDF and send the relevant pieces. This practical loop is detailed in the guide to mailing a heavy PDF.

Send the smallest clean copy

Once the file fits, keep the content readable and complete. Resist uploading the original full-resolution PDF to a sharing site just to bypass a limit: a compressed copy at a sensible size is usually all the recipient needs. Your whole workflow stays in the browser, so the document never leaves your device and stays private until you hit send.