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Compress PDF · WhatsApp

How to compress a PDF for WhatsApp

WhatsApp allows large documents, but sending a 40 MB scan over mobile data is slow for you and storage-hungry for everyone in the group. Compressing first makes the send near-instant and is kinder to phones.

Because FernPDF runs in the browser, this works directly on your phone: open the tool in Chrome or Safari, compress, then share the downloaded file to WhatsApp.

Group chats make the case stronger than a one-to-one send: a heavy PDF shared to a 30-person group multiplies the download cost by everyone in it, not just you, and it sits in every one of those phones' storage afterwards. Compressing before you share is a small step for the sender and a meaningfully smaller one for everyone downloading it on the other end, especially on an older phone with limited storage.

Step by step

  1. 1On your phone or computer, open the Compress PDF tool.
  2. 2Drop or select the PDF.
  3. 3Pick “Recommended” (or “Strong” for scans).
  4. 4Download, then attach it in WhatsApp as a document.
No upload · no account · no watermark
FAQ

Common questions

Yes, it runs in Safari on iPhone and Chrome on Android. No app needed.

Related guides
How to shrink a PDF's file size on MacHow to shrink a PDF's file size on WindowsHow to shrink a PDF's file size on iPhoneHow to shrink a PDF's file size on AndroidHow to shrink a PDF's file size on ChromebookHow to shrink a PDF's file size on Linux

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