Shrink your PDF for email without uploading it anywhere.
Most email services cap attachments at 20-25MB. Gmail, Outlook, and Yahoo all enforce these limits. When your PDF exceeds them, you're stuck — and the workarounds aren't great.
You could upload to Google Drive or Dropbox and share a link. But that means your document lives on someone else's server, and the recipient needs the right permissions. For contracts, medical records, or financial documents, that's a real concern.
Drag your oversized PDF into the compress tool — or click to browse. The file stays on your computer the entire time.
Select "Balanced" for most emails, or "Maximum" if you need to hit strict size limits like 1MB. Preview the output quality before downloading.
Save the compressed PDF and attach it to your email. Most 15MB files compress to under 5MB with the Balanced setting.
Understanding the limits helps you choose the right compression level. Here's what each major email provider allows:
25MB per email. Larger files automatically redirect to Google Drive links.
20MB for Outlook.com. Corporate Exchange servers may enforce 10MB limits.
25MB per email attachment.
20MB standard. Mail Drop handles up to 5GB via iCloud links.
If your PDF needs to stay under 1MB (common for government forms and job applications), use ModernPDF's compression and select the "Maximum" setting. For email-friendly sizes, "Balanced" usually gets a 15MB file under 5MB.
Think about what you email as attachments: contracts, tax returns, medical records, financial statements, legal filings. These are exactly the documents you wouldn't want sitting on a third-party server.
When you use a typical online PDF compressor, your document gets uploaded to their servers, processed, then sent back. During that round trip, your file exists on infrastructure you don't control — sometimes for hours or days before it's deleted (if it's deleted at all).
ModernPDF's compression runs entirely in your browser using WebAssembly. Your PDF is processed by your own computer's processor. No network request is made. No copy exists anywhere except your device. For documents heading into an email, this is the only architecture that makes sense.
It depends on the content. Text-heavy PDFs compress less than image-heavy ones. A scanned 15MB PDF typically compresses to 2-4MB. A 5MB document with photos might drop to 1-2MB. The "Maximum" compression setting prioritizes file size over image quality.
At "Balanced" compression, most people can't tell the difference. Text remains sharp. Images lose some detail at higher compression levels, but it's rarely noticeable for email attachments. You can preview the result before downloading.
Try the "Maximum" compression setting. If it's still too large, consider splitting the PDF into smaller parts using our Split PDF tool and sending them as separate attachments.
Yes. Your file never leaves your device. ModernPDF processes the PDF using your browser's built-in capabilities. No data is transmitted to any server. This is fundamentally different from tools like Smallpdf or iLovePDF that upload your file for processing.
Currently, compress works one file at a time. If you need to compress several PDFs, process each one individually. Each compression takes just a few seconds since there's no upload wait time.
Shrink files to fit any attachment limit. Free to start. Private. Pro for unlimited use.
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