Cropping in preview is a simple task that can help focus attention on the most important parts of an image or document. It can also save file space or reduce download times. Preview includes a number of tools that can make this process easier and more efficient, especially for large images or documents.
To crop an image in preview, open the target file in the app and click the Show Markup Toolbar button (or the Crop button on the Touch Bar). Then, use your mouse or trackpad to select a rectangular section of the document, framing out everything that you don’t want to keep. You can resize the selection using any of the round blue handles on the corners of the frame, or choose Tools > Adjust Size to display a menu with various units of measurement.
Preview can crop just about any file type that it supports, including images and PDFs. It can even crop Photoshop PSD files without the need for a dedicated photo editing program like Adobe Photoshop. Another quick tip: While you’re working on a rectangular selection, you can press Command + C and Command+ N to create a new document with the copied contents. This is a quicker way to get a new file that you can print or send to a printer, but it doesn’t preserve the transparency of your empty selection areas. This isn’t the most convenient workflow for a lot of users.