How to Resize a Canvas Relative to an Edge in Photoshop
If you’re creating an image in Photoshop yet you don’t know the exact measurements you want in the beginning, it’s always best to start with a bigger canvas size. It’s easy to decrease the size around your image once you’ve figured out how big you want it.
Let’s say I am going to create a line of text for the home button of my website. I am going to first start with a blank 200 by 200 canvas and add the text I want. My image now looks like this:
It obviously is not the right size for a link. The next step it to shrink the canvas size UP FROM THE BOTTOM in order to get the right size.
The first step is to click on the “Image” tab at the top of the screen. Then, choose the “Canvas Size” option. A window should appear that looks like this:
Let’s say I want to trim 100px off of my image from the bottom. I would then change the number in the “Width” box to 100. Now, this next step is the most important and the reason I am writing this post. The small box in the “Anchor” section designates which area to trim off of the canvas. If I didn’t change any options and pressed OK, the 100 pixels would trim equally off of the top and bottom, and some of my text would be cut off. Instead, click on the bottom, middle arrow, and watch as the rest of the arrows change. Now, your Anchor box should look like this:
Next, click OK. Your image should resize by cutting off 100 pixels from the bottom. The anchor arrows can be used to remove or add pixels from any side of the canvas. They can be extremely convenient and remove the hassle of rearranging layers, text, etc.