The Problem with Large PDFs
PDFs are the standard format for sharing documents, but they have an Achilles' heel: file size. A scanned contract might be 5 MB. A product catalog with high-resolution images might be 80 MB. A construction blueprint or engineering drawing can exceed 200 MB. When the file is too large for email, too slow to upload, or too heavy for the recipient to download on a mobile connection, you need a strategy.
This article covers seven proven methods for sending large PDF files, starting with the simplest and progressing to solutions for extremely large documents.
Method 1: Compress the PDF
The first thing to try is compression. A good PDF compressor reduces file size by resampling images to a lower resolution, converting color images to grayscale where appropriate, removing embedded fonts that are not used, and stripping metadata and unused objects from the file structure.
Compression works best when the PDF contains high-resolution images or was created by a tool that does not optimize output by default. A 50 MB scan-based document can often be compressed to 5 to 10 MB with minimal visible quality loss.
When to use: Always try compression first. It is the fastest and simplest solution, and it often brings the file under the email attachment limit in one step.
Method 2: Split the PDF into Smaller Parts
If compression alone is not enough, split the document into multiple smaller files. A 60 MB, 100-page report can be divided into five 20-page files of roughly 12 MB each -- well within email limits. Include all parts in the same email or send them in sequence with clear labels ("Part 1 of 5," "Part 2 of 5," and so on).
When to use: When compression gets you close to the limit but not under it, or when the recipient needs the full document and lossy compression is not acceptable.
Method 3: Share via Cloud Storage
Upload the PDF to a cloud storage service -- iCloud Drive, Google Drive, Dropbox, OneDrive, or Box -- and share a link. This completely bypasses email attachment limits. Most cloud services support files up to several gigabytes.
Advantages of cloud sharing:
- No size limit. Share files of any size, from a few kilobytes to multiple gigabytes.
- Access control. Set permissions to view-only, comment, or edit. Require a password or limit access to specific email addresses.
- Expiration. Set links to expire after a certain date, which is useful for sensitive documents.
- Version tracking. If you update the file, recipients who access the link will see the latest version.
When to use: When the file is too large for email even after compression, when you want to maintain control over access, or when the document may be updated after sharing.
Method 4: Use a File Transfer Service
Dedicated file transfer services like WeTransfer, SendAnywhere, or Swiss Transfer are designed specifically for sending large files. You upload the file, enter the recipient's email address, and the service sends them a download link. Most free tiers support files up to 2 GB.
When to use: When you need to send a one-time transfer to someone who is not on the same cloud platform, or when you do not want to create a shared folder.
Method 5: Remove Unnecessary Pages
Before sending, ask yourself whether the recipient actually needs every page. A 150-page report might include appendices, reference materials, or cover pages that are not relevant to the recipient. Extracting only the pages they need can dramatically reduce file size and makes the document easier to read.
When to use: When you are sharing a subset of a larger document -- specific chapters, selected invoices from a batch, or relevant pages from a manual.
Method 6: Convert to a Lower-Quality Format
If visual quality is not critical and the document is primarily text, consider these conversions:
- Color to grayscale. Removing color data typically reduces file size by 60 to 70 percent.
- Grayscale to black-and-white. For text-only documents, black-and-white (1-bit) encoding produces the smallest possible files.
- Lower DPI. Reducing scan resolution from 300 DPI to 150 DPI cuts the pixel count (and file size) by roughly 75 percent. Text remains readable at 150 DPI on screens.
When to use: When the recipient will view the document on screen rather than print it, or when the document is text-heavy without important color elements.
Method 7: Flatten the PDF
PDFs with interactive form fields, comment layers, embedded multimedia, or editable annotations carry extra data that inflates file size. Flattening the document bakes all these layers into the page content and removes the interactive structures. The visual result is identical, but the file is smaller and simpler.
When to use: After filling out forms or adding annotations, especially when the recipient does not need to interact with those elements.
Quick Reference: Email Attachment Limits
Here are the 2026 attachment limits for major email providers:
- Gmail: 25 MB
- Outlook / Microsoft 365: 20 MB (up to 150 MB on some enterprise plans)
- Yahoo Mail: 25 MB
- Apple Mail (iCloud): 20 MB (Mail Drop supports up to 5 GB via a temporary link)
- ProtonMail: 25 MB
Remember that these limits include all attachments in the message combined, plus the email body and any formatting. A "25 MB limit" effectively means you should keep attachments under 22 to 23 MB to leave room for the email itself.
A Practical Workflow for Large Files
- Check the file size. Right-tap the file in the Files app to see its size, or check in your PDF app.
- Compress first. Try medium-quality compression. Check the output.
- Remove pages if possible. Strip out anything the recipient does not need.
- Flatten if applicable. Remove interactive layers.
- If still too large, split or use a cloud link.
Manage Large PDFs with PDF Creator
PDF Creator - Scanner & OCR includes every tool mentioned in this article: compress, split, extract pages, convert to grayscale, flatten, and more. When you need to get a PDF from your phone to someone else's inbox, PDF Creator gives you multiple ways to make it fit.