Compress PDF for email
Get a PDF under the attachment limit of Gmail, Outlook, Yahoo and iCloud.
or drop files anywhere on this page
Your files stay in this browser. Nothing is uploaded.
About Compress PDF for email
Email services cap how big a message can be, and a PDF straight from a scanner or a phone can be over the cap on its own. This page is Compress PDF with its Target size set to 20 MB, the lowest cap among the big consumer email services, and it hands back the sharpest version of your PDF that fits under it.
Nothing is sent anywhere while it works: the file is rewritten in this browser tab, and it leaves your device only when you attach it to an email yourself.
How it works
- Add the PDF you want to send. You can add several; each is fitted under the size on its own, so see the note below about sharing one email.
- Target size is already set to 20 MB (fits most email). If you only use Gmail, Outlook.com or Yahoo Mail, Custom size lets you go up to their 25 MB.
- Click Compress to 20 MB and wait for the note under the file name.
- Download the result and attach it to your email.
Email size limits
Every one of these limits applies to a whole email, so all the attachments on it share the space.
| Service | Limit | What it covers |
|---|---|---|
| Gmail (personal) | 25 MB | All attachments together; over that, Gmail swaps in a Google Drive link |
| Outlook.com | 25 MB | Attached files; larger files can go as a OneDrive link, up to 2 GB |
| Yahoo Mail | 25 MB | All attachments in one message together |
| Outlook app with an Outlook.com or Gmail account | 20 MB | The whole email, attachments included |
| iCloud Mail | 20 MB | The whole message; Mail Drop sends larger files as a link, up to 5 GB |
| Outlook app with a work Exchange account | 10 MB | The default, which your organisation can change |
| Microsoft 365 work or school mail | 35 MB | The default for sending (36 MB to receive), which admins can change |
Several PDFs on one email
Target size fits each file under the size you choose, one file at a time. When several PDFs go on the same email, divide the limit between them: for three PDFs on a Gmail message, choose Custom size and type 8 MB, and the three together stay under 25 MB. For the Outlook app, whose limit counts the message itself, leave a little room for the text of the email.
What fits in 20 MB
Our ten-page scan, 300 dpi colour on Letter paper, was 4.87 MB, about 490 KB a page. At that rate a scan passes 20 MB at around 40 pages. When it does, Target size keeps as much of the scan as the limit allows:
- At 300 ppi and JPEG 80%, our scanned pages took about 394 KB each: about 50 pages in 20 MB.
- At 200 ppi and JPEG 80%, about 218 KB each: about 90 pages.
- At 144 ppi and JPEG 45%, about 89 KB each: over 200 pages.
When a link beats an attachment
Past about 200 scanned pages, a scan only fits in 20 MB at a setting that reads well on screen but prints soft, and past about 750 it does not fit at all. Gmail and Outlook.com already offer a Drive or OneDrive link for large files, and iCloud Mail has Mail Drop. Sending a link keeps the full-quality file, and the person you send it to downloads it when they need it.
Frequently asked questions
So the same file also gets through the Outlook app and iCloud Mail, which allow 20 MB, whoever you send it to. If you know everyone involved uses Gmail, Outlook.com or Yahoo Mail, choose Custom size and type 24 to keep a little more detail.
Yes. Only the pictures in the PDF are re-encoded. Typed text stays text, so it can be searched, copied and read aloud as before.
No. It is compressed in this browser tab, and nothing leaves your device until you attach it to an email.
The limit covers the whole email, so other attachments count too, and the recipient's own mail service can have a lower limit than yours; Microsoft gives the Outlook app a 10 MB default for work accounts on Exchange. Try a smaller size with Custom size, such as 8 MB.
Yes. Choose 10 MB in the Target size list; that is the default Microsoft gives the Outlook app with a work Exchange account. Custom size takes any other figure your organisation uses.
Yes. Only the pictures are re-encoded. Links, typed text and page sizes stay exactly as they were, so the PDF opens and reads the same in the recipient's mail app.
You get the smallest version it could make, and the note says what is taking the space. Split PDF on the result screen can cut it into parts to send on separate emails, or use a Drive, OneDrive or Mail Drop link instead.
Other sizes
Related tools
This tool ran entirely in your browser and nothing was uploaded. Your Recent files list keeps a copy of local files under 5 MB until you clear it. How your files are handled.