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Compress PDF for Email

Shrink a PDF until it will actually send — with the real attachment limits explained, including why files “under the cap” still bounce. Text stays selectable, nothing is uploaded, and it is completely free.

Add PDF
Compress
Save PDF

Drop your PDF here

or click to browse · PDF files · scanned documents compress best

Converts on your device — your PDF is never uploaded
pages
images
original
images are
Compression method Smart
Smart recompresses the images inside your PDF and leaves text and vector graphics untouched — so text stays selectable and searchable.
How much
Target file size 2 MB
The tool tries several quality and resolution combinations and keeps the best result that fits under your limit.
Extra saving
Convert images to grayscale
Useful for scanned text documents — often cuts another 20–40% with no loss of readability.
BEFORE Original
document.pdf
File size
Pages
AFTER Compressed
document-compressed.pdf
File size
Reduction
Text
✓ Saved to your device as document-compressed.pdf

Compress a PDF to Send by Email

Shrink a PDF until it will actually send. Pick a target that sits comfortably inside your provider’s attachment limit, compress in your browser, and attach the result — with the text still selectable and nothing uploaded anywhere along the way.

The trap nobody mentions: email attachments are encoded for transport, which inflates them by about a third. A 20 MB file leaves your outbox as roughly 27 MB — which is why a file “under the limit” still bounces. Target well below the stated cap.

Real Attachment Limits

ServiceStated limitSafe target
Gmail25 MB10 MB
Outlook.com20 MB10 MB
Corporate mail serversOften 10 MB5 MB
Older or government systems2–5 MB2 MB

And remember the limit applies at both ends. Your 20 MB attachment may leave Gmail happily and be refused by the recipient’s corporate server, which is the most common reason a message silently fails to arrive.

Do Not Bother Zipping It

A PDF is already compressed internally, so putting it in a ZIP typically saves a few percent at most — nothing like the 70–90% that recompressing the images achieves. Meanwhile you have handed the recipient an archive to extract, which is genuinely awkward on a phone and sometimes blocked outright by corporate mail filters.

When to Send a Link Instead

If the document genuinely needs to stay large — a print-ready brochure, a portfolio of photographs — do not compress it into mush to force it through email. Upload it to any cloud storage service and send the link. The recipient gets the full-quality file, nothing bounces, and your message stays small.

Compression is the right answer when the size is waste: scans at needless resolution, phone photos of paperwork, images far larger than any screen will show. It is the wrong answer when the size is genuine content.

Frequently Asked Questions

How do I compress a PDF to send by email?

Add the file, pick a target that fits comfortably inside your provider's limit - 10 MB is a safe choice for Gmail and Outlook - then press Compress and attach the result.

What is the attachment limit for Gmail and Outlook?

Gmail allows attachments up to 25 MB and Outlook.com up to 20 MB. Many corporate mail servers are stricter, commonly 10 MB, and the receiving server also has a say - so aim well below the stated cap.

Why did my email bounce when the file was under the limit?

Because attachments are encoded for transport, which inflates them by roughly a third. A 20 MB file can arrive as about 27 MB of email. That is why targeting 10 MB rather than 25 MB avoids a great deal of frustration.

Should I zip the PDF instead?

Rarely worth it. PDFs are already compressed internally, so zipping typically saves only a few percent - and it makes the file harder for the recipient to open, especially on a phone. Compressing the PDF itself is far more effective.

What if the file is still too big?

Send a link instead of an attachment. Any cloud storage service will host the file and give you a URL, which avoids attachment limits entirely and lets the recipient download at their convenience.

Will the recipient notice the compression?

For screen reading, usually not. Email attachments are almost always read on screen rather than printed, and screens need far less resolution than paper.

Is my document uploaded to compress it?

No. The PDF is compressed inside your browser and never leaves your device before you attach it yourself.

Is it free?

Completely free, with no sign-up, no watermark and no limit on how many files you compress.

Related: Need to combine files? Merge PDF. Compress PDF (all options) · to 2 MB · to 500 KB · Compress a scanned PDF