How to Send a PDF by Email: Attach, Shrink or Link

Quick Answer

Most PDFs go out the plain way: attach the file and press Send. It only fails when the whole email is over a limit, and Google gives 25 MB for a personal Gmail account. In Gmail, Google also says that when your total attachment size is over the limit, Gmail removes the attachment and adds it as a Google Drive link in the email, so a Gmail sender is often rescued without doing anything.

These steps cover a computer and the web mail apps. We did not cover sending a PDF from an iPhone or Android phone, so this page does not answer that.

Attach

All three programs work the same way: write a new message, add the file, press Send.

Gmail. On a computer, go to Gmail, click Compose, click Attach at the bottom, choose the PDF and click Open. These are the steps on Google's page on sending attachments. Gmail does not list .pdf among its blocked file types.

Outlook. In new Outlook, in a new message, select Attach File from the Insert group on the Message tab, then choose the file under Browse This Computer. See Microsoft's guide to attaching files in Outlook. Outlook's limit is 20 MB or 25 MB depending on which Microsoft page you read, and 10 MB by default on a work Exchange account. Our Outlook attachment size limit post has the full table and explains why the two Microsoft pages disagree.

Apple Mail. Open the message you are writing, click the Attach button (the paperclip) in the toolbar, then Attach Files, select the PDF and click Choose File. You can also drag the file in from the desktop or Finder. See Apple's guide to sending attachments in Mail. The same page says to send documents as PDFs instead of in their original format when the person you are writing to uses Windows.

If you have a whole folder rather than one file, that is a different job. Our post on how to send a folder by email covers zipping it.

Shrink

If the PDF is over the limit, you can make the file smaller on a Mac with Preview. Apple warns that a compressed PDF may be of lower quality than the original, and that the resulting size and image quality vary with the options you pick. Apple's page gives no size figure, so we cannot say how much smaller yours will be.

1. Open the PDF in the Preview app.
2. Choose File > Export.
3. In the Quartz Filter pop-up menu, choose Reduce File Size.
4. Type a new name in the Export As field, then click Save.

Use a new name in step 4. Apple says that if you click Save on the old name, you replace the existing file, and you then have no original to go back to.

Below the filter, Apple lists three tick boxes: Create Linearized PDF (fast loading in a web browser), Optimize images for screen (reduces file size) and Save images as JPEG (uses image compression). These are all on the same Preview page.

We found no Microsoft page that gives a built-in way to shrink a PDF on Windows, so we do not give one. Preview is the Mac way.

Protect

There are two kinds of password to know about, and they guard different things.

A password on the PDF itself. In Preview, Apple says you can protect a PDF with a password that must be entered to open the file.

1. Open the PDF in Preview and choose File > Export.
2. To keep the original unlocked, type a new name for the copy.
3. Click Permissions, then select Require Password To Open Document.
4. Enter a password, retype it to verify, click Apply, then click Save.

Apple says the changes take effect the next time the PDF is opened. Send the password a different way from the email, such as a text message or a phone call. That is our advice, not Apple's. Apple's page makes no claim about how strong the protection is, and neither do we.

A passcode on the message. In Gmail, click Turn on confidential mode at the bottom right of the window, then set an expiration date and passcode. Google says these settings affect both the message text and any attachments, and that if you choose SMS passcode, recipients get a passcode by text message. On a work or school account, Google says to contact your administrator to make sure you can use it.

Gmail's blocked-file page does not list a password-protected PDF as blocked. It names password-protected archives with archived content, which is about zip files, not PDFs.

Send a Link

A link is the way out when shrinking is not enough, or when you want a PDF that can expire or be paused. You upload the file somewhere and paste the link into the email. The sections below show what each route adds.

These are US dollars for one person, before tax. Where a paid figure is shown, it is for the entry plan that does the job and the yearly figure is the one the page's Annual or "Billed yearly" view shows. We could not confirm today's paid prices for WeTransfer, DocSend or Papermark's paid plan, so we leave them out.

• Mail Drop. Apple says you can send attachments up to 5 GB with Mail Drop, and that recipients have 30 days to download them. For the steps and the cases where it does not apply, see our Mail Drop on Mac post.
• Google Drive. Google says all Google accounts come with up to 15 GB of storage. Google One Basic is 100 GB at $19.99 a year. Google also says attachments count toward your Google storage.
• Dropbox. Dropbox's plans page gives the free Basic plan 2 GB to store and share your files. It lists Password protect files and Brand your files to share on Standard, which is $15 a user a month when billed yearly (the page's default view), so $180 a user a year. We could not read the monthly-billing price.
• WeTransfer. WeTransfer's plan limits page allows 10 transfers or 3 GB in any 30 days on the free plan. We did not re-read WeTransfer's prices today.
• Papermark. Papermark's pricing page lists a Free plan with 50 links and page-by-page analytics (the page showed euros to us; the Free plan costs nothing in any currency).

A single PDF almost always fits a free route. A paid tool earns its place when you send PDFs again and again and want your name on the page, a password on the link and a way to see when it was opened. Email itself does not tell you. Our post on the Gmail read receipt explains what Gmail can and cannot show.

Loop

Loop does not shrink a PDF, and for one PDF sent once to one person it adds nothing: attach it. Loop is a Mac app that turns a PDF into your own link, which you paste into your email. It suits people who send PDFs often and want a few things the free routes leave out.

1. Drop the PDF on the Loop icon in the menu bar, or choose File > New Link.
2. Link Copied. Loop copies the link, ready to paste.
3. Paste it into your email. You write and send the email yourself.

• A page in your name. The reader opens the PDF in their browser, with no app and no account. You can set your brand name, logo and colors.
• A password and an expiry on the link. Both are settings on each link. Expiry is optional and defaults to Never.
• View only. Turn off Allow Downloads and the reader can only read the PDF in the browser.
• A Mac notification. Your Mac shows a notification the first time each visitor opens the link, and when it is downloaded. That is once per reader's browser per link, for opens and for downloads, and only while Loop is running. The link row shows how far a reader got, such as "Read 3 of 8 Pages", which is the furthest page reached, not the pages read.

Loop is Mac only on your side. The person you send it to can use any browser, on a Mac, a PC or a phone.

Limits

Loop is not the right tool for every PDF. Here is what it does not do:

• It does not encrypt the PDF. The password guards the link page. If you allow downloads, the reader gets the original PDF with no password inside it. For a locked file, set a password in Preview first, as in Protect above, then share that file.
• It does not shrink the PDF. Use Preview for that.
• It does not send the email. It copies the link and you paste it into your mail program.
• It does not work from an iPhone or Windows. The sender needs a Mac running macOS 14 or later.
• It does not alert you by email or phone. Alerts are Mac notifications while Loop is running.
• It does not prove who opened a link. A typed email address is checked for format only, and a forwarded link opens for whoever has it.
• It needs a Cloudflare account. Setup signs in to Cloudflare once.

We do not promise a maximum file size.

Cost

Attaching a PDF is free. Mail Drop does not count against your iCloud storage, and the free plans of Google Drive, Dropbox and Papermark cost nothing. Loop is $49 once for one person.

Loop's files are stored in your own Cloudflare account, free up to 10 GB. Past that, Cloudflare bills you. Cloudflare's pricing page, updated 30 October 2026, lists $0.015 per GB-month with no data-transfer charge for downloads. Cloudflare may also ask for a card when you switch storage on.

Loop includes a 14-day free trial that starts on first run, and Loop asks for no payment to begin it. During the trial a small "Shared with Loop" badge shows on the pages your clients see, and it goes with a licence.