Document Size vs. Canvas Size in Photoshop

When I started working with Adobe Photoshop, I didn’t understand the difference between “document size” and “canvas size.”  Coming from a painting background, I viewed my “canvas” as the area I had to work on. I translated this, in Photoshop, to mean the photo or scrapbook page I was working on.  That is not necessarily true.

After some exploration, I learned that while my canvas size can be my document size, my document size is not necessarily equal to my canvas size.  Confusing? Let’s take a closer look.

In Photoshop, we can determine our document size in several different ways:

1. Click on the right-pointing arrow at the bottom of your document, and in the pop-up window, select “Document Dimensions.” This will show the size of your document in inches.  (Cycle through the other options available and see if they might be helpful for you as you work!)

2. In the top Menu, go to Image > Image Size.

3.  And yet another way is to right-click on the top of your document. A window will open, offering you several options, one of which is to check your Image Size.

I prefer Way #3 because by selecting Image Size,   I am able to view my image size in both pixels and inches.  I can also double-check my Resolution at the same time.

The image below is a Facebook Cover, with the dimensions of 850 pixels by 315 pixels (or 2.833 inches by 1.05 inches) at 300 dpi.

In this instance, the canvas size is equal to the document size; there is no area around the document on which we can work.  There are times, however, where we will need to work on the edges of a document, and need extra space to do so. In cases like this, we would want to increase our canvas size. To open the Canvas Size dialogue box we can:

1. On the top Menu bar, go to Image > Canvas Size, or

2 Right click on the top of our document and select Canvas size.

Once in the Canvas Size dialogue box, we will need to put in the Width and Height by which we would like to increase our canvas.  By clicking on the downpointing arrow, to the right of the Width box, we can choose which format we would like to work in. I have my option set to pixels.

Since this is a very small image, and I don’t need a large canvas to work on, I am only going to increase my canvas size by 35 pixels. To do this, I enter 35 in both the Width and Height Boxes (with Pixels selected), making sure that the Relative Box is checked.

Now there is a transparent area around the image, which will allow me extra space to work, if needed.

NOTE: If your image is your Background layer, when the canvas size is increased, it will take on the the color of the Background color in your Color Picker OR you may use the Canvas Extension Color Option (at the bottom of the dialogue box) to choose the color you would like your canvas to be.   If you would like a transparent canvas, you will need to double-click on your Background layer to unlock it.

The other option that you see visible in the Canvas Size dialogue box is the “Anchor” box.  This is where you can choose the positioning of your image on your new canvas.  Click in the center of the  Anchor box if you would like your image centered, as I have in the image above.  Click on any of the arrows in the box to position your image in that position on the new canvas.

Now this is a lot of information… but what do we do with it? How is it helpful to us? There are 3 specific reasons why this information is helpful for me.   But what about you?  I am continually amazed at the different perspectives we all have on things. Give a scrapbook kit to 10 different ladies, and you will most likely get 10 different styles of layouts, all from the creators unique perspective.  So before I tell you how I use this information, will you tell me how you use it or how you think you might use it in the future?

Leave a comment here in the blog post, or if you prefer, send me a Private Message (PM) via the Forum.  I will be back next week to tell you how I use this information and to share your own ideas!

Photoshop Elements Users:  You are able to access your Document Size information in the same way as Option #1 as noted above.  For Option #2, go to  Image > Resize > and then you will see both the Image Size and Canvas Size options.  Option #3 is not available in Photoshop Elements.

The image in this tutorial was a Facebook Cover that I created using  my All Wrapped Up Word Art and Kit.   If you would like to download and use this image on your own Facebook Page, you may download it by clicking on the image below.  Enjoy the 30% off sale on all of the All Wrapped Up Products, now through December 31st!