Reduce Photo Size for Email on Mac (Mail’s Image Size Menu and More)

1. Start a new message and drag the photos in, or use the paperclip button to attach them.
2. Look at the message header, below the Subject line. Mail shows an Image Size pop-up once an image is attached.
3. Open it and choose Small, Medium, Large or Actual Size.
4. Mail shows the resulting message size beside the menu. Pick the smallest option that still looks acceptable for the recipient.

Mail does not publish the pixel dimensions of each preset, so we are not going to quote any. Use the size readout next to the menu and judge by that. If the pop-up is missing, you may have attached the file as a link or in a different format, or the message may be in plain text. Switch it to Rich Text with Format > Make Rich Text.

A current phone or camera photo is thousands of pixels wide. Email does not need that. Attachments also grow in transit, because email encodes them as text, so a file that looks just under a limit can still bounce. Mail providers set their own caps, so check yours before you send a batch.

The fix is the same as for any image: fewer pixels first, then lower quality. We tested on one 4032 × 3024 JPEG (2.73 MB) with sips. It is a synthetic image, so your numbers will differ.

Ten photos at the original size is about 27 MB in our test. Ten at 1600 pixels is about 2.4 MB.

In Finder, select the photos and open them together in Preview. Press Command-A in the sidebar to select every page, choose Tools > Adjust Size…, enter the width, then File > Export Selected Images…. Pick a new folder so the originals stay untouched.

From Terminal, one line resizes every JPEG in a folder into a new one:

mkdir -p small
for f in *.jpg; do sips -Z 1600 "$f" --out "small/$f"; done

That keeps the photos as JPEGs, which every recipient can open. For more ways to do this at scale, see batch resizing images with Automator.

Mail Drop, built into Apple Mail with an iCloud account, uploads large attachments to iCloud and sends the recipient a download link instead. It kicks in when your mail provider would reject the message. Apple documents its size and expiry limits on its Mail Drop support page, so check them there.

The catch for privacy: the files do sit on iCloud for a while, and recipients get a link, not an attachment. If you want the photos to stay on your Mac and arrive as ordinary attachments, shrink them instead. Our guide to getting PDFs small enough to email covers the same trade for documents.

Yes. Select the photos in Photos, choose File > Export > Export Photos…, set Photo Kind to JPEG, pick a JPEG Quality and a Size (Small, Medium, Large or Full Size), then choose a folder. Drag the exported files into your message. HEIC photos from an iPhone become JPEGs this way, which also avoids problems for recipients who cannot open HEIC. See HEIC to JPG on a Mac for the details.

For a few photos, Mail’s Image Size menu is the right tool. It takes two clicks and costs nothing. Preview and sips cover the cases where you want the files shrunk before attaching them. Smol is also not instant: a sips loop beats it on small files.

Smol earns its $29 (once, one Mac) when email is a routine, such as photos from a job site, a school year of pictures, or a folder mixing HEIC, JPEG and PNG. Drop the folder in, pick a quality, and each file gets a smaller copy next to the original with a _compressed suffix. It runs on your Mac and uploads nothing. It resizes to fit inside 2000 × 2000 pixels by default and strips location data, which is usually what you want before sending photos to strangers. Compare options in the best image compressor for Mac roundup, or buy Smol.