Documents are supposed to be small. Then someone scans a 200-page contract at 600 dpi, a designer exports a print-ready brochure, or a tender requires 40 PDFs with drawings — and the email bounces. This guide explains how to send large documents and PDFs, starting with the simplest fix and ending with methods that have no practical size limit.
Why are some documents so large?
Text is tiny — a 300-page novel as plain text is well under 1 MB. Documents grow because of what is embedded in them:
- Scans. Every scanned page is a picture. A colour scan at high resolution can be several megabytes per page.
- Images and charts. Uncompressed photos pasted into Word or PowerPoint keep their full camera resolution.
- Print-ready files. Press PDFs carry high-resolution images, embedded fonts and colour profiles.
- Drawings and plans. Architectural and engineering PDFs exported from CAD carry vector detail for every line (see send CAD files).
- Bundles. A due-diligence pack, a tender submission or a court bundle is many documents, often in a folder structure that matters.
How do I make a large PDF smaller?
If you need to email it, shrink it first — this is often the quickest fix:
- Adobe Acrobat: use Reduce File Size or Optimize PDF.
- macOS Preview: File → Export, then choose the Reduce File Size Quartz filter. It compresses images aggressively, so check the result.
- Word and PowerPoint: use Compress Pictures before exporting to PDF.
- Scanners: scan text at 200–300 dpi in greyscale instead of 600 dpi colour.
Zipping a PDF rarely helps much: the images inside are usually already compressed. And if the document must stay print-quality — artwork, plans, signed originals — don't shrink it; send it at full size by one of the methods below.
What are the ways to send large documents?
Limits for free personal plans as of 5 November 2026, from each vendor's help pages.
| Method | Size limit | Recipient experience | Copy stored on a server? | Sender online? | Best for |
|---|---|---|---|---|---|
| Email attachment | 20–25 MB per message | Opens in the inbox | Yes, in mailboxes | No | Small PDFs |
| Gmail with Drive link | Your 15 GB Google storage | Link to Drive | Yes | No | Gmail users |
| iCloud Mail Drop | 5 GB, 30 days | Download link | Yes | No | Apple Mail users |
| Cloud drive share (Drive, OneDrive, Dropbox) | Your storage quota | Preview online, comment | Yes, until deleted | No | Documents reopened for weeks |
| Transfer service (WeTransfer free) | 3 GB, 3-day expiry | Download link | Yes, temporarily | No | One-off sends |
| StrongFolder (P2P) | None set by the service | Downloads straight from you | No | Yes | Big PDFs, document folders, privacy |
Email with a cloud link
The least friction for most people: Gmail replaces an attachment over 25 MB with a Google Drive link, Outlook can attach OneDrive files as links, and iCloud Mail can switch to Mail Drop. Every provider's numbers are in email attachment size limits.
A shared cloud folder
Best when documents are living: a contract that goes through rounds of comments, a shared policy library, a folder the client will return to for months. The recipient can preview without downloading. The price is a stored copy on the provider's servers and your storage quota.
A file transfer service
Fine for a one-off package under a few gigabytes when you don't want to stay online. The files are stored for a few days and then deleted.
A direct link with StrongFolder
Choose the PDFs or the whole document folder, copy the link and paste it into your email in
place of an attachment. When the recipient opens it, the download starts at once — straight
from your computer over an encrypted connection. Files are never uploaded to or stored on a StrongFolder server. The folder tree
arrives as you built it: 01 Contract, 02 Annexes, 03 Drawings.
Free · in your browser · no sign-up
How do I send a folder of documents in the right order?
Numbered subfolders and file names are often part of the submission: a tender or a court bundle must keep its structure. Two tips:
- Number the folders and files (
01_,02_) so they sort the same way on every system. - Send the folder, not a ZIP, so the recipient doesn't have to extract it and gets the same tree straight away. See send a folder without zipping.
Is it safe to send confidential documents online?
Every method above encrypts the connection in transit. The difference is the stored copy: email and cloud links leave the document on servers until someone deletes it; a direct transfer doesn't. If a direct connection is impossible (strict corporate firewall, some mobile networks), the encrypted stream passes through a StrongFolder relay (TURN) server. The relay forwards the data and does not store it.
For regulated workflows — signatures, audit logs, retention rules, access approvals — use the system your organisation requires (an e-signature service, a data room, a managed file transfer platform). StrongFolder is built for fast person-to-person delivery, not for compliance record-keeping. More in secure file sharing.
When is StrongFolder not the best choice for documents?
- The document fits in an email. Just attach it.
- People need to comment, edit or sign online. Use a cloud editor or e-signature tool.
- The recipient opens the link days later. The link works while the sender keeps sharing. When the sender clicks Stop Sharing or closes the tab, the files are no longer available.
- You need a formal audit trail of who downloaded what and when.
Summary
To send large documents, shrink the PDF if quality allows, attach it if it fits under 20–25 MB, and otherwise send a link: a cloud link for documents people will keep working on, and a direct P2P link for big PDFs and whole document folders you want delivered without a stored copy. For every method by size, see how to send large files.