Trying to send a PDF over WhatsApp. The upload bar climbs slowly. Or fails. Or the recipient never receives it.
What's actually going wrong
WhatsApp officially supports documents up to 2GB, but practical limits are much smaller. Upload speeds bottleneck on slow connections. Recipients on poor connections may struggle to receive large files. And WhatsApp Web has stricter limits than the mobile app.
For most use cases, keeping PDFs under 16MB matches WhatsApp's image/video limits and ensures fast sending.
The quick fix
Compress PDF before sending. Most files compress to under 5MB — fast to upload, fast to receive, no failed sends.
For PDFs with images that you're sending for casual sharing rather than print, aggressive compression is fine. Quality is plenty for screen viewing.
If that didn't work
If WhatsApp keeps failing, try sending from WhatsApp mobile rather than Web. Mobile handles documents more reliably.
For very large PDFs, share via cloud link in WhatsApp instead of as a document. Recipient clicks the link to download. Works for any size and bypasses WhatsApp's document handling entirely.
Prevent it next time
Compress PDFs habitually. Use mobile WhatsApp for documents over a few MB. And share large files via cloud link.
FAQ
What's WhatsApp's maximum document size?
Officially 2GB, but practical limit is bandwidth and recipient handling. Under 16MB sends reliably; over 100MB often struggles regardless of official limits.
Does WhatsApp compress documents I send?
No — documents are sent as-is. Images and videos get WhatsApp's compression; PDFs don't. Compress yourself before sending if size matters.
Can I send a PDF in a WhatsApp group?
Yes, same limits as individual chats. Large files take longer to deliver to all group members.
Why does my WhatsApp Web fail with PDFs that work on mobile?
WhatsApp Web has stricter document handling. Use mobile for sending; Web works fine for receiving.
Fast WhatsApp PDFs start with compression. Compress in Flint and send.