Email attachments
Compress a PDF for Email
Get a scanned contract, an invoice, or a long report under your inbox's attachment limit. Pick a target well below the cap, and the tool compresses the PDF in your browser.
- No upload or account
- Starts at a 2 MB target
- Measured result
Your file never leaves this device — everything happens locally in your browser.
Compressing more than one PDF? Try batch compression.
Target size
Starting…
Processing happens entirely on this device — nothing is uploaded.
Your file never leaves this device — everything happens locally in your browser.
Your file never leaves this device — everything happens locally in your browser.
Attachment limits
How big an attachment can be
- Gmail (personal)
- 25 MB. Anything larger is swapped for a Google Drive link.
- Outlook.com
- 20 MB, per Microsoft's Outlook help.
- Work or school (Exchange)
- 10 MB by default. Administrators can set their own limit, higher or lower.
The exact numbers and where they come from are in the guide: how to reduce a PDF's size for email.
Picking a target
Which size to aim for
Aim well under the limit, not right at it.
Sending from Gmail
25 MB limitAim for 10 to 15 MB. That leaves room for encoding and anything else in the message.
Sending to a work inbox
10 MB limitAim for 5 to 7 MB against a 10 MB organizational limit.
Not sure what the limit is
Safe defaultKeep the 2 MB default. Even with encoding, it fits under every limit listed here.
Several PDFs in one message
Shared limitThe limit counts all of them together. Batch compress them to the same target, then add up the results.
Your document
What changes, and what doesn't
A contract or invoice that's all text usually just needs its internal structure repacked, so nothing on the page changes. Scanned pages and image-heavy reports shrink by having their images re-encoded, at the highest quality that still fits your target.
FAQ
Frequently asked questions
What's a safe PDF size for email attachments?
Most providers cap attachments somewhere in the 10–25 MB range. Gmail's documented limit, for example, is 25 MB. Email sends attachments as Base64 text, which adds roughly a third to the bytes sent, so a file close to the stated limit can still bounce. Getting comfortably under 2–5 MB is safer than aiming right at the ceiling.
My email bounced saying the attachment was too large — what happened?
Attachments are encoded for sending, which adds about a third to their size, and the limit can also count the message text and any other attachments. So a file that looks like it should fit can still be rejected. Compressing to a target well below the stated cap gives you headroom.
Will compressing my contract or invoice change its content?
Your wording isn't edited. Compression repacks the file and re-encodes any images in it, so a contract that's all text looks exactly the same afterwards. Two exceptions: if the tool has to turn pages into images to reach your target, the text stops being selectable and form fields stop working (the result screen tells you). And a certified digital signature stops validating once the file is rewritten, so compress before signing.
Can I just send a link instead of compressing?
You could, if you're comfortable uploading the document to a file-sharing service first. That puts a copy on that service's servers. Compressing it here happens on your device, and the attached file then only travels through your email provider, like any other attachment.