Compress a PDF for email
Open the free Compress PDF tool, pick a compression level, and download a smaller PDF that fits within Gmail (25 MB), Outlook (20 MB) or your client's attachment cap.
- Free forever
- No watermark
- No paid plan
- Free for commercial use
- Google Ads funded
- Files stay on your device
Email attachment limits haven't changed much in years, but PDFs have. A scan from a modern multifunction printer can easily hit 30–80 MB for ten pages. Whenever you go to send it, the provider bounces back with 'attachment too large'.
The fix is to compress the PDF before sending. Pelican's Compress tool re-encodes the document's images at a smaller size — usually shrinking the file by 60–90% — while keeping text crisp and selectable.
Email attachment limits, in numbers
Gmail: 25 MB. Outlook / Microsoft 365: 20 MB. Yahoo Mail: 25 MB. Many corporate mail servers: 10 MB. Sending to a US government inbox is often capped at 5–10 MB. If your PDF is over those numbers, it needs compression or a file-share link.
How the compression works
PDFs are usually large because of embedded images, not text. The Compress tool finds the embedded images and re-encodes them at a lower resolution and JPEG quality. Text stays vector — it doesn't get rasterised — so it remains sharp at any zoom level.
Three preset levels: Low (subtle savings, near-original quality), Medium (the right pick for most scanned documents), and High (smallest file, visible image softening).
When compression won't help
If your PDF is mostly vector text and contains very few images, there's little to compress. In that case the file is already as small as it gets.
Privacy
Compression runs in your browser. The PDF isn't uploaded to a server.
Why the size limit exists in the first place
Email was designed to be a lightweight messaging system, not a file transfer protocol. Servers along the path queue each message in memory, scan it for viruses, run it through spam filters, and replicate it across redundant storage. A 50 MB attachment costs many times its own weight in server load, and a misrouted attachment can clog a recipient's mailbox indefinitely. The 10-25 MB cap most providers enforce isn't arbitrary — it's the largest size that keeps email cheap and responsive at the scale of billions of messages a day.
The practical upshot is that the limit isn't going to be relaxed. Compressing your PDF until it fits is the right long-term solution; emailing a 'sorry, too big' attachment back and forth is not.
What to do if the file still won't fit
If Medium compression isn't enough and High isn't enough either, you're probably dealing with a high-resolution colour scan that genuinely needs the resolution. Two options. First: split the document into smaller pieces and send them as multiple emails — works fine for two or three pieces, gets annoying past that. Second: use a file-share link (Google Drive, Dropbox, OneDrive, WeTransfer) and email the link instead of the attachment. Recipients don't have to set up an account to follow most public share links.
Compression and confidential documents
Compressing in a browser-based tool makes more sense for confidential content than uploading to a cloud compressor. The Compress tool reads the PDF into your browser's memory, runs the re-encoding locally via WebAssembly, and downloads the result directly. There's no server round-trip and nothing to delete afterward — the file simply never existed outside your tab.
FAQ
- How much smaller will my PDF get?
- Scanned documents typically shrink 60–90%. Vector-heavy PDFs (mostly text) shrink less, sometimes only 10%.
- Will text become blurry?
- No. Text stays vector. Only embedded images are re-encoded.
- What level should I pick?
- Start with Medium. Drop to High only if Medium isn't small enough.
- Will the output have a watermark?
- No. Output from the Compress tool is unbranded.
Related free tools
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