How to Crop a Photo on Mac (2026 Guide)

Your Mac already has two built-in tools that crop photos without installing anything: Photos and Preview. Photos is faster for quick edits inside your library, while Preview is better for one-off files sitting in Finder or downloaded from the web. Here's exactly how to use both, plus how to lock an aspect ratio and crop without losing quality.

Crop a Photo Using the Photos App

1. Open Photos from your Dock or Applications folder.
2. Select the photo you want to crop, then click Edit in the top-right corner.
3. Click the Crop tool (the icon that looks like two overlapping corners).
4. Drag the corner handles inward to adjust the crop area, or drag inside the frame to reposition the photo.
5. To lock a specific ratio, look in the sidebar that appears once you're in Crop mode — choose Square, a preset like 4:5 or 16:9, or Custom to set your own ratio.
6. Click Done to save. Photos keeps the original file intact, so you can always revert.

Crop a Photo Using Preview

1. Open the image in Preview — right-click the file in Finder and choose Open With → Preview if it doesn't open there by default.
2. Show the Markup Toolbar by clicking the pen-in-a-circle icon at the top of the window (if it isn't already visible).
3. Select the rectangular selection tool, then click and drag over the area of the photo you want to keep.
4. Crop the selection with Tools → Crop in the menu bar, or use the keyboard shortcut Command + K.
5. Save your changes with Command + S, or use File → Export first if you want to keep the original uncropped file as a backup.

Preview doesn't offer preset aspect ratios the way Photos does — you're drawing a freeform rectangle — but you can watch the pixel dimensions in the selection as you drag if you need a specific size.

If the source is a screen capture, the Mac screenshot cropping guide also covers selecting only the needed area when you capture it and refining the result afterward in Preview.

Tips for a Cleaner Crop

• Duplicate first. In Preview, use File → Duplicate (or export a copy) before cropping so you always have the original to fall back on. Photos does this automatically — a crop is non-destructive until you explicitly revert.
• Crop before you resize. If you also need a specific pixel size (say, for a profile photo or thumbnail), crop to the right aspect ratio first, then resize — cropping after resizing can reintroduce quality loss.
• Use the rule of thirds. In the Photos app, turning on the grid overlay while cropping makes it easier to keep your subject off-center for a more balanced composition.
• Watch your resolution. Cropping removes pixels, so a tight crop on a low-resolution photo can look soft once it's back at full size on screen.

When You Need More Than a Crop

Built-in Mac tools are great for a quick, exact crop, but they stop there — no filters, no aspect-ratio presets built for specific social platforms, and no way to fill in extra space around a photo instead of cutting it away. The browser-based Instasize crop tool, also available on iOS and Android, adds:

• Platform-ready aspect ratio presets for Instagram, TikTok, YouTube, and more, so you crop once to the exact size a platform expects.
• Magic Fill, which extends the edges of a photo with AI-generated background instead of cropping out parts of the shot you want to keep.
• Filters and adjustments to finish the edit after cropping, without switching apps.

FAQs

Can I undo a crop in the Photos app?

Yes. Open the cropped photo, click Edit, and choose Revert to Original — Photos stores the pre-crop version even after you've closed and reopened the app.

What's the keyboard shortcut to crop in Preview?

Select your crop area first, then press Command + K. There's no shortcut to select the crop area itself — that part is always a manual drag.

Can I crop to an exact pixel size on Mac?

The Photos app only offers ratio presets (square, 4:3, 16:9, and a few others), not exact pixel dimensions. Preview shows you the selection size as you drag but won't let you type in exact numbers. For a specific pixel size, crop roughly on Mac, then resize precisely in an app like Instasize.

Does cropping reduce image quality?

Cropping itself doesn't compress or degrade the remaining pixels, but it does reduce the total resolution of the photo since you're keeping fewer pixels. A crop from a high-resolution original will still look sharp; a crop from an already-small image may look softer once displayed at a larger size.

Is there a free way to crop photos on Mac?

Yes — both Photos and Preview are free and pre-installed on every Mac, so you don't need to buy or download anything for basic cropping.