-
First
click on the Crop tool on the Tool Palette. This will activate the Crop
Tool Options Tool Bar at the top of the PhotoShop screen.
-
Locate
the Width field and right click on it. If pixels are
NOT selected, select Pixels. If pixels are selected no change is
necessary.

-
Right
click on the Height field and if necessary select pixels.
-
In the
Width and Height fields enter the Width and Height values in pixels that
you want to crop the image to.
- For images destined for
the web set the resolution to 72 pixels/inch.
-
In the
example image below, the values are set to a Width of 400 px and a Height
of 400 px x resolution 72. This will crop the image to a perfect square
that will be 400 x 400 pixels at a resolution of 72 ppi.
-
Put your
cursor on your image and drag out a crop selection area. You will see that
the crop area is constrained and will crop whatever crop selection area
you select to the width and height settings you made on the Options Tool
Bar.
-
Click
on OK to crop the image.