# How to send large documents and PDFs

Source: https://help.strongfolder.com/en/guides/send-large-documents/
Updated: 2026-11-05

> To send large documents, first try reducing the PDF size so it fits an email (20–25 MB). If it still doesn't fit, send a link instead: a cloud drive for documents people will reopen, or a direct peer-to-peer transfer such as StrongFolder for big PDFs and whole document folders, with nothing uploaded or stored on a server.

1. **Open StrongFolder** — Go to [strongfolder.com](https://strongfolder.com) or click the StrongFolder Chrome extension.
2. **Add the documents** — Pick the PDFs, or the whole folder of documents (for example a tender package or a case file) to keep its structure.
3. **Send the link** — Copy the link and paste it into your email or chat in place of an attachment.
4. **Keep the tab open** — The recipient downloads straight from your computer, so keep the tab open until they finish, then click Stop Sharing.

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.

**Key facts**

- **Email limits are tiny:** about **25 MB** in Gmail and Yahoo, **20 MB** in iCloud Mail.
- **First try shrinking the PDF** — scans and images are usually what makes it big.
- **Cloud links** are best when people will reopen or comment on the document for weeks.
- **Direct P2P** (StrongFolder) sends big PDFs and whole document folders with no upload and nothing stored. No size limit set by StrongFolder. The practical limits are free disk space on the recipient's device, connection speed, and how long both devices stay online.
- The trade-off: **your tab must stay open** until the recipient finishes.

## 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](https://help.strongfolder.com/en/guides/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:

1. **Adobe Acrobat:** use *Reduce File Size* or *Optimize PDF*.
2. **macOS Preview:** *File → Export*, then choose the *Reduce File Size* Quartz filter. It
   compresses images aggressively, so check the result.
3. **Word and PowerPoint:** use *Compress Pictures* before exporting to PDF.
4. **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 2026-11-05, 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](https://help.strongfolder.com/en/guides/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`.

[Send files now](https://strongfolder.com)
## 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](https://help.strongfolder.com/en/guides/send-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](https://help.strongfolder.com/en/guides/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](https://help.strongfolder.com/en/guides/send-large-files/).

## FAQ

### How do I send a PDF that is too large to email?

Reduce its size first (Acrobat's Reduce File Size, macOS Preview's Reduce File Size filter, or re-scanning at a lower resolution). If it is still above about 20–25 MB, send a link: Gmail adds a Google Drive link automatically, or use a transfer service or a direct P2P link.

### What is the maximum size of a document I can email?

About 25 MB in Gmail and Yahoo Mail, and 20 MB in iCloud Mail; Microsoft's pages give 20–25 MB for Outlook.com. Work accounts have limits set by the admin. See our email attachment size limits page for details.

### How do I send many documents at once and keep them organised?

Send the folder instead of individual attachments. Folders are sent as folders: subfolders and file names are kept, nothing is zipped. Saving a whole folder with its structure uses the File System Access API: Chrome, Edge, Opera and other Chromium browsers on a computer. Other browsers can download the files one by one or as a ZIP.

### Is it safe to send confidential documents this way?

WebRTC encrypts every data channel with DTLS, so the file stream is encrypted in transit on every connection. Files are never uploaded to or stored on a StrongFolder server. For documents that need signatures, access logs or legal retention, use your organisation's approved system.

### Can the recipient open the documents later?

Once downloaded, the files are theirs to keep. The link works while the sender keeps sharing. When the sender clicks Stop Sharing or closes the tab, the files are no longer available.