How to compress a video on your Mac

Your Mac can shrink a video by itself. QuickTime Player exports a smaller copy at 1080p, 720p or 480p, Finder's Encode Selected Video Files does the same from a right-click, and iMovie lets you set the quality while it shows the file size. Koi does it in one drag, with Light, Balanced or Strong and the new size shown before you save. None of them upload the video.

We make Koi, so read the Koi part with that in mind. Everything about Koi here is what version 1.13 does. Apple's steps, and the email limits below, come from Apple's and Google's own help pages, checked October 21, 2026.

• Gmail: attachments up to 25 MB. Above that, Gmail takes the file out and puts in a Google Drive link instead.
• Apple Mail with Mail Drop: up to 5 GB, sent as a link through iCloud that lasts 30 days. Apple lists the limits.
• Discord, WhatsApp and the rest change their limits, and some differ by plan. Check their own help pages for today's number, then aim a little under it.

Three things decide a video's size: how many pixels it has, how long it runs, and how hard the picture is compressed. The size in pixels is the biggest lever. A 4K phone clip dropped to 1080p is usually a fraction of what it was, and few people watching in a chat window will notice.

1. Open the video in QuickTime Player.
2. Choose File, Export As, then 1080p, 720p or 480p. Sizes bigger than your video are dimmed.
3. For 1080p or 4K, pick Smaller File Size in the Format menu. That uses HEVC. Greater Compatibility uses H.264.
4. Name it, pick a folder and click Save.

720p and 480p always use H.264. Apple suggests 480p for posting online. Whatever you pick, the copy is a .mov. Apple's export guide has every option.

Control-click the video in Finder and choose Encode Selected Video Files. Pick a lower resolution, then choose between higher quality and working on more devices. Apple describes it in the QuickTime Player guide's automation tips. It's handy for a batch, since it takes every video you selected.

iMovie is free from Apple and is the only built-in app that shows the size as you go. Select the video, choose File, Share, File, set Resolution, then set Quality to Custom and drag the slider. The estimated file size updates as you drag. Click Next and save it. Apple's iMovie guide has the details.

1. Start dragging the video in Finder or on your desktop.
2. While you're still holding it, press and hold Shift. The video wheel opens round your pointer.
3. Drop the video on Compress. Its window opens with the video playing on the right.
4. Pick Light, Balanced or Strong under Preset.
5. Under Video size, keep the original or pick 2160p down to 480p.
6. Read the Result: the original size, about how big the copy will be, and how much smaller that is.
7. Click Compress. The copy lands beside the original and shows in Finder.

• Compress encodes the picture in HEVC, which gets a lot smaller than H.264 at the same quality.
• When the settings wouldn't make it smaller, it says Already this small and the button stays off.
• The original is never touched. A MOV stays a MOV.
• It runs on your Mac with Apple's AVFoundation. Nothing is uploaded.

• Make it shorter. Half the length is about half the size. Trim the video before you compress it.
• Crop it. A screen recording of one window doesn't need the whole screen. Crop the video first.
• Take the sound out if nobody needs it. Mute the video.
• Need it to play everywhere? Koi's Edit Video exports an MP4 with Encoding set to Fast (H.264), at Low, Medium or High, with each size shown before you save.

• One video for an email, free and now: QuickTime Player at 720p.
• You need to land under a number, like Gmail's 25 MB: iMovie's Custom quality or Koi's Compress, since both show the size before you save.
• A folder of clips: Finder's Encode Selected Video Files takes them all at once.
• You shrink videos every week and don't want to open an app: Koi, one drag from wherever the file is.

• HEVC is small, but some older PCs and apps can't play it. If the person you send it to sees no picture, send an H.264 copy instead.
• A video that's already been squeezed, like one saved from a chat app, won't drop much more. Lower the size in pixels instead.
• Compressing again and again loses a little each time. Always start from the original.
• Chat apps may compress what you send anyway. If quality matters, send a link or a file instead of a video message.

Shrinking a PDF instead? Read how to compress a PDF on Mac. Everything else the wheel does is on the Shift wheel page. Used to HandBrake? Read about simpler HandBrake alternatives.

QuickTime, Finder and iMovie are free. Koi has no free plan: Pro is $20 a month, or $192 a year, after a 3-day free trial that needs a card. Lifetime is paid once, from $59. The Shift wheel uses no AI, so it never counts against Koi's usage. See the plans.