Gmail has a 25MB attachment limit. Outlook caps at 20MB. If your PDF is too large, it bounces. If you compress it badly, it comes back blurry and unprofessional.
Here's how to reduce your PDF size for email without making the document worse.
What Makes a PDF Large?
Most oversized PDFs come down to one or two causes:
- Embedded images — A single high-resolution photo can add 3–5MB. Documents with multiple photos or scanned pages bulk up fast.
- Unoptimised fonts — Some PDF exports embed entire font families, even when only a fraction of the characters appear in the document.
- Hidden metadata — Word and Photoshop often store revision history, thumbnail previews, and authoring data inside the file. None of it is visible, but it adds weight.
- Redundant data — Older PDF exporters sometimes duplicate internal resource references.
For text-only documents, compression gains are modest. For image-heavy or scanned files, reductions of 50–80% are common.
Smart Compression vs. Destructive Compression
There are two ways a compressor can reduce file size, and the difference matters.
Destructive compression converts every page into a low-resolution image — essentially rephotographing your document and discarding the original content. Text becomes unselectable, fonts blur, and the document loses much of its usefulness. Avoid tools that work this way.
Smart compression works within the document structure. It reduces image resolution to screen-appropriate quality (around 144 DPI — sharp on any monitor), removes unused font data, strips hidden metadata, and cleans up the internal structure. The result looks the same on screen but takes up significantly less space.
TryMyPdf's Compress PDF tool uses smart compression. Your text stays selectable, the document remains a proper PDF, and the output is ready to email.
How to Compress a PDF for Email
- Open the Compress PDF tool — Go to TryMyPdf Compress PDF in your browser.
- Upload your file — Drag your PDF into the upload area or click to browse.
- Click "Compress PDF" — The tool processes your file and reduces the size automatically.
- Download and check the result — Open the compressed file, zoom into the images, and read through a few lines of text before sending. Make sure quality is acceptable.
- Attach and send — If the file is now within your email provider's size limit, you're done.
When Compression Has Limits
Some PDFs won't shrink much no matter what you do:
- Text-only documents are already lightweight — there's little to compress.
- Previously compressed files won't reduce significantly with a second pass.
- Vector-heavy technical drawings already store data efficiently.
In these cases, the practical alternatives are to remove pages you don't need using Split PDF, or to upload the file to Google Drive or Dropbox and share a link instead of attaching it directly.
Printing vs. Screen
One important consideration: compression that's fine for email may not be suitable for professional printing. If the file is going to a commercial printer, don't compress it heavily — use the original, full-resolution version. Compressed PDFs are optimised for screen viewing and standard printing, not large-format or high-quality commercial print jobs.
Privacy
TryMyPdf processes all files over HTTPS. Uploaded files and outputs are automatically deleted within an hour. Nothing is stored or shared.
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