How to Change the Size of a Photo in iPhoto

Digital photo files can be quite large. If you are emailing or posting your images to the web, such as in a blog, you will want to resize them for quick uploading and downloading. You can resize your images in iPhoto using the export function. By resizing, you decrease the resolution of the photo, which makes it ideal for sharing but less ideal for printing.

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Your camera settings determine the file and photo size.

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Open iPhoto and select the image that you want to resize from the photo browser.

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From the File menu (iPhoto 4) or Share menu (iPhoto 5), select "export". A new dialog box will appear with three tabs.

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From the first tab, named "File Export", select the file format you wish to use. Choose JPEG, TIFF or PNG as your file type to allow for resizing. JPEG is the most versatile and will allow you to also select the quality of the image to save.

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Select from small, medium and large files (and resulting images), or you can choose "custom" to specify a specific height and width. Click "Export" and choose where to export your file to. Click "OK" and you are done!