How to Compress Your Photos Library on a Mac

Published October 19, 2026.

A Photos library grows on every device you own, and on a Mac with a small internal drive it can crowd out everything else. Compressing it on your iPhone works, but a Mac is often the better place: a bigger screen for comparing results, a keyboard, and a computer that can keep working on a long batch while you do something else.

HEVCut runs as a native Mac app. This guide covers which library it works on, how it handles originals stored in iCloud, the settings to check, and the Mac-specific details: keyboard shortcuts, the summary panel, and compressing SD cards.

Quick answer

1. Install HEVCut from the Mac App Store (macOS 26 or later) and allow access to Photos.
2. Click Compress on Home, check the settings under the gear, and click Compress.
3. Keep working in other apps while it runs. Don't quit HEVCut until the run ends.
4. Review the results, then delete the originals you no longer need. They go to Recently Deleted in Photos.

HEVCut on the Mac

Since version 10.2, HEVCut on the Mac is built as a Mac app rather than running as an iPad app on the Mac. It has the same tools as on iPhone and iPad: Compress, Duplicates, Clutter, Swipe, and External drive. It's the same app you can download from the App Store on iPhone and iPad.

Version 10.2.3 for Mac fixed video compression failing on some Macs. If videos wouldn't compress on your Mac in an earlier version, update and try again. See what's new for the full release history.

Which library HEVCut compresses

HEVCut works on your Mac's System Photo Library, the library Photos uses for iCloud Photos. If you keep more than one library, Apple says that other applications use photos from the System Photo Library even when you've opened a different one in Photos. To compress another library, make it the System Photo Library first.

With iCloud Photos on, the compressed versions HEVCut saves sync to your other devices like any new photo or video. When you delete the originals, Apple's usual rule applies: they sit in Recently Deleted for 30 days, then leave your devices and iCloud.

Compress your library

Originals stored in iCloud

If Photos is set to Optimize Mac Storage, Apple keeps the full-size originals in iCloud and stores smaller versions on your Mac when space is limited. HEVCut needs the original to compress an item, so it downloads each one first. Items that are only in iCloud carry a cloud badge ("Stored in iCloud") in the list, and the progress dock reads "Downloading 3 of 12" while it fetches them.

If your Mac goes offline mid-run, HEVCut skips the items it can't download, tells you once with iCloud Download Unavailable, and carries on with items already on the Mac. Run it again later to pick up the rest.

Check your settings first

Settings live under the gear (Settings) in the Compress toolbar, separately for Video Compression and Photo Compression. Each has four presets: Gentle, Standard, High, and Max. Standard is the default. A few things to know before a big run:

• Videos are capped at 1080p by default, and Max at 720p. To keep 4K videos at 4K, turn on Keep original resolution. It's free. Keep 4K or drop to 1080p? explains the trade-off with numbers.
• Photos are capped too. Gentle and Standard limit the long side to 3840 pixels, High to 2560, and Max to 1080. Keeping a photo's full resolution is only possible in Fine-tune, which needs Pro.
• Format: HEIC by default, or AVIF under Format in Photo Compression.
• Live Photos: with Keep Live Photo off, which is the default, a compressed Live Photo becomes a still photo. Turn it on to keep the motion. It's available with HEIC only.

HEVCut only offers items it estimates will shrink by at least 5%, and if a result comes out larger, it keeps the original.

What to expect from photos

In a small test of 8 photos, run with HEVCut's photo encoder on a Mac, Standard HEIC saved a median of 62.4%, Gentle 40.7%, and High 80.8%. High's extra savings came with a large measured loss of fine detail at full size, partly because it also scales photos down to 2560 pixels. These are examples from one small set, not a promise for your library, which may save more or less. For format and quality choices, see How to compress a photo on iPhone and AVIF vs HEIC.

Working with HEVCut on a Mac

Keep working while it compresses

On iPhone, iOS decides how long a background run may continue. The Mac has no such limit for HEVCut: compression keeps going while you switch to other apps. HEVCut encodes one video at a time.

Quitting HEVCut stops the run. On the next launch you'll see Compression Interrupted, and you can start again from Compress. Items that finished before you quit are already saved.

The summary panel

In a wide window, Compress, Duplicates, and Clutter show a summary panel at the side. In Compress it shows how much your library can shrink, a breakdown for videos and photos, how much you've saved so far, the progress of the current run, and the Compress button. Use Hide Summary or Show Summary in the toolbar to toggle it. In a narrow window, the same summary moves into the main view.

Keyboard shortcuts

• ⌘, opens HEVCut's settings screen from the menu bar.
• ← and → in Swipe sort the photo or video in front of you: left marks it for deletion, right keeps it. Nothing is deleted until you review the deletion list. See How to clean up your camera roll by swiping.

Review and delete

Compression never replaces anything on its own. Each compressed item is saved as a new item next to its original, with the original's capture date, location, favorite status, and albums.

• One item: open it to compare, then choose Keep Compressed or Revert.
• The whole batch: the dock at the bottom of Compress shows something like "48 originals · Frees 6.2 GB". Click Delete to remove those originals, or click Undo in the toolbar to delete the compressed versions and keep every original.

Deleted originals go to Recently Deleted in Photos, where Apple keeps them for 30 days. On a Mac, you'll find it under Utilities in the Photos sidebar.

Compress an SD card or drive on the Mac

The External drive tool works the same on a Mac as on iPhone. If your Mac has an SD card slot, insert the card (Apple lists which Macs have one), click External drive on Home, and pick the card or a folder on it. HEVCut writes a compressed copy next to each file and never touches the originals unless you delete them, which on a drive is permanent. Library and drive compression never run at the same time. The details are in Compress videos on an SSD or SD card.

Frequently asked questions

Related guides

• How to compress iPhone videos in the background (iOS 26)
• Keep 4K or drop to 1080p? Choosing compression settings on iPhone
• Compress videos on an SSD or SD card from your iPhone, iPad or Mac
• Exact, similar, near-duplicate, and burst photos
• Stop paying for iCloud storage
• See every HEVCut feature