How to Make Photos Smaller for Texting From a Mac

1. Open the photo in Preview.
2. Choose Tools > Adjust Size.
3. Set the unit to pixels, keep Scale proportionally ticked, and type 1600 into Width or Height.
4. Choose File > Export, set Format to JPEG, and drag the Quality slider down. The dialog shows the estimated size.
5. Save the copy, then drag it into Messages.

Use Export, not Save, so the original stays full size. The longer walkthrough is in reduce an image’s file size in Preview.

Yes, one command in Terminal. This writes small copies into a folder and leaves the originals alone:

mkdir -p small
for f in *.jpg; do sips -Z 1600 -s format jpeg -s formatOptions 60 "$f" --out "small/$f"; done

More flags are in the sips command guide, and the Automator batch resize guide covers a point-and-click version.

We took one 4032 x 3024 JPEG (5.2 MB) and measured. The fixture is synthetic, so treat the numbers as a guide to the pattern, not a promise for your photos.

A phone screen shows 1600 pixels across with room to spare, so there is little to gain from sending more. Size depends mostly on pixel count, then on quality. Cut pixels first.

Lower the size first, and touch quality second. We also saved the same 5.2 MB photo with the sips quality words, with no resize:

Even “low” at full resolution is bigger than a 1600 px copy at quality 60 (229 KB), and it looks worse because blocky artifacts show up on large flat areas. Resizing to 1600 px and keeping a moderate quality gives a smaller and cleaner result. Also avoid sending PNG: it is lossless, so a photo saved as PNG is far larger than the same photo as JPEG. Screenshots are the exception, since text and flat color stay sharp in PNG.

It is an iPhone setting in the Messages settings that makes the phone send smaller images in Messages. Turn it on if you text from the phone and want small files by default. It does not affect photos you send from the Mac, so resize those yourself.

Note the reverse problem: iMessage can already shrink photos, and a reader who needs full quality should get them by AirDrop instead. We cover that in does AirDrop compress photos.

Usually the format. HEIC photos do not open everywhere, mostly on older Windows PCs and some Android phones. Exporting as JPEG fixes it. See HEIC to JPG on Mac for the free methods.

For one or two photos, Preview is enough and free. Smol is overkill for a single text.

It earns $29 once when you do this often or in bulk: drag a folder of photos in, or right-click them in Finder, and get a small copy of each beside the original. By default Smol also strips location and camera tags from the copies, which is handy before you text photos to people you do not know. Nothing is uploaded. It is not the fastest tool: a sips loop beats it on speed. Details at /buy, or see the best image compressor for Mac comparison.