How to Change the Canvas Size in Photoshop
You’ll learn multiple ways to change canvas size in Photoshop, from adding even borders to extending the canvas on one side. We’ll use the Relative option for precise additions, anchor the expansion, and set a canvas extension color. A quick example shows adding space for a caption strip and the difference between Relative and absolute sizing.
Step-by-step instructions
Open Canvas Size
Go to Image → Canvas Size…
Shortcut: Windows Alt+Ctrl+C / Mac Option+Command+C.
Choose your Units (inches, pixels, percent).
Add an even border around the image
Check Relative to add to current size.
Enter Width: 5 and Height: 5 with Units set to Inches to add a 5-inch border on all sides.
Set Canvas extension color to White.
Click OK.
Extend canvas on one side only
Open Image → Canvas Size… again (Alt/Option+Cmd/Ctrl+C).
Switch Units to Pixels or Percent.
Click the Anchor grid’s left box to pin content left (empty space will be added on the right).
Set Canvas extension color to Gray.
Enter a Width increase (e.g., 10%); click OK. If you need more space, repeat with 100%.
Use the new area (e.g., add a caption)
Select the Type Tool (T).
Click in the added strip and type your text (e.g., a title or caption).
Know Relative vs absolute sizing
Image → Canvas Size…
Uncheck Relative to set the total target size (e.g., entering 55 makes the total dimension 55 units).
Check Relative to add the specified amount to each applicable side (e.g., +55 adds on both left and right for width).
