How to Compress a PDF to Send on WhatsApp (Under 100 MB)
WhatsApp documents max out at 100 MB. Most people don't hit it — until they try to send a phone-scanned 20-page contract or a 50-photo travel album exported as PDF. Here's how to shrink any PDF to fit, without uploading sensitive content to a third-party site.
The problem
You scanned a passport, ID card, or signed agreement on your phone. The "Save as PDF" output is 80–150 MB because phone scanners default to high-resolution images. WhatsApp rejects the document, your contact is waiting, and most online compressors require uploading the file you're trying to keep private.
Use the tool now
Open the compress pdf tool and follow the steps below.
Step-by-step
- 1
Move the PDF to a device with PDFShed access
Mobile browsers work, but the desktop browser is faster and more memory-tolerant for large scans. AirDrop or upload to your laptop if needed.
- 2
Open the Compress PDF tool
Drop the file into the embedded tool below. Processing is local — your scan never leaves the device.
- 3
Select "High Compression"
For ID cards, signed contracts, and screenshots, High Compression cuts size 70–85% while keeping text and signatures readable.
- 4
Download and send via WhatsApp
Save the compressed PDF, attach in WhatsApp as a Document. It should send in under 5 seconds on Wi-Fi.
Pro tips
- •WhatsApp Web has the same 100 MB limit as the phone app — file size, not platform, is the issue.
- •If your phone scanner produces 150+ MB PDFs regularly, lower the scan resolution in the scanning app to 200 DPI. 300 DPI is overkill for phone scans.
- •For large image batches, use JPG to PDF with quality set to 75% — that bakes compression into creation.
- •Telegram allows 2 GB documents, Signal 100 MB. Pick the messenger that fits the file if compression isn't enough.
Frequently asked questions
Does WhatsApp compress PDFs automatically?
No. WhatsApp compresses photos and videos but never modifies documents. What you upload is what your contact downloads.
Can I send a compressed PDF to multiple WhatsApp groups?
Yes. Once compressed and sent once, WhatsApp caches the file — forwarding to other groups is instant.
Will compression remove the digital signature?
Cryptographic signatures (DocuSign, Adobe Sign) survive compression. Image-based signatures (a photo of a signature) survive but may soften slightly at aggressive settings.
My PDF is still over 100 MB after max compression. What now?
Use Split PDF to break it into two halves, send each as a separate document. Or use Compress + reduce image resolution in JPG to PDF if it's mostly photos.