How to Resize, Rotate, and Crop Images

Resize

Resizing an image is one of the most basic and frequently used tools inside Photoshop. Begin by opening a file into Photoshop. Once you have a file opened, you'll be able to access the image size tool.

Accessing the image size tool

The main tool used for resizing is image size. To access the image size tool, choose Image > Image Size or press Alt+Ctrl+I. When you become more familiar with Photoshop, you'll be using the image size tool a lot so it is a good idea to remember the hotkey for this tool.

Pixel Dimensions vs Document Size

Inside the image size tool, you'll find that there's two way to resize the width and height:

Pixel Dimensions

Use the pixel dimensions area if you want to resize the image to a pixel dimension. For example, if you want to resize the photo to a more suitable size for displaying on the web, you would edit the pixel dimensions. If you want to resize an image to 640x480 pixels, simply enter in 640 pixels and 480 pixels in the width and height setting.

You may notice that when you enter in one of the settings, the other one changes automatically. This is because the constrain proportions is enabled and it is usually indicated by the icon beside the setting. Usually for photos, you want to keep the settings constrained so that your images don't stretch. Stretching of the image is like watching standard 4:3 aspect ratio video on a wide-screen TV. The image becomes stretched and objects look irregular.

Document Size

Use the document size area if you want to resize the image for print. For example, if you want to resize a photo so that it can be printed on a 4x6 inch paper, enter in those settings in the document size area. If you're trying to resize a photo to 4x6 inches but it won't let unless you uncheck constrain proportions, enter one of the setting and we can crop the excess amount off later. Make sure that when you enter in the width and height, that the number for both the width and height be equal or the greater than the output size you want. For example, use 4x6.5 inches instead of 4x5.333 inches. We can crop off the excess 0.5 inch later using the crop or canvas size tool.

Resampling

When you are upscaling or downscaling the image (making the image bigger or smaller), you'll need to resample the image. On the bottom of the image size tool, you'll find the resample image checkbox and a drop down menu with different methods of resampling.

When you uncheck resample images, the pixel dimensions area will be disabled. In order for the image to change pixel dimension, it needs to be resampled. If you edit the width and height in the document size area, the resolution will change accordingly because it too needs to be resampled. Basically, anything resizing that requires pixels to be added or remove will need resampling.

When resampling up, the sharpness of the image may decrease.

When you have resampling checked, you'll be presented with five different ways to resample the image.

Nearest Neighbor

Produces the sharpest-looking results but at the cost of jagged edges. This method is used mostly for illustrations without anti-aliasing.

Bilinear

Looks at the pixels and adds new pixels based on the average between the group of pixels.

Bicubic

Produces better results than bilinear. This method uses more complex calculations to create smoother results than bilinear. The only downside compared to the bilinear method is that it may take slightly longer to process.

Bicubic Smoother

This is a version of the bicubic resampling method that produces smoother results. This method is useful for enlarging images.

Bicubic Sharper

This is a version of the bicubic resampling method that produces sharper results. This method is useful for reducing the image size. However, it can cometimes oversharpen certain areas of an image. If that happens, choose the normal bicubic method instead.