It no longer has anything to do with actual canvas fabric, but changing your canvas size in GIMP lets you change the pixel dimensions of your image without changing any of the actual image content. This gives you room to expand or a quick way to crop, depending on what you need.
The InstaGuide to Changing Canvas Size in GIMP
Here’s how you can give yourself the perfect canvas size. This method is so quick, that you can do it in only two steps!
Step 1: Open the Image menu, and click Canvas Size.
Step 2: Enter your chosen settings, and click Resize.
That’s all there is to it! Usually, when you’re changing canvas size, it’s because you’re increasing it in a single direction to adjust composition, but this method lets you extend in any or all directions as needed.
That should be enough guidance for most of your canvas adjustment needs, but you may also have noticed that there are a couple of other options in the Image menu related to canvas size and they’re worth knowing about, so let’s take a look at them while we’re at it.
Automatically Adjusting Canvas Size in GIMP
Sometimes you’ll need to adjust your canvas size without knowing the exact size you need, and GIMP can automatically calculate the new canvas size for you using the two additional commands found in the Image menu: Fit Canvas to Layers and Fit Canvas to Selection.
GIMP allows you to create layers that contain image content larger than your current canvas size, which often happens when pasting new images into GIMP using the direct copy/paste method. Fit Canvas to Layers will instantly shrink or expand the canvas as needed to match the exact dimensions of your largest layer.
It’s also possible to quickly resize your canvas using Fit Canvas to Selection, which can be used to quickly crop your images if you don’t want to bother with the actual crop tool. Just a few clicks allow you to select the exterior of your current layer and instantly crop your canvas to match that size.
Adjusting a Canvas For Printing
As you may or may not know, screen resolution is usually 72 or 96 DPI (unless you’re using a Mac or other computer with a Retina-style screen). Printed images should be 300 DPI for optimal print quality, and you may need to adjust your image resolution to print it properly.
If you’re used to working with Photoshop, you’ll have to adjust your thinking a bit to the way that GIMP handles image/canvas size and resolution. The principles are the same, but you’ll find the correct command by opening the Image menu and choosing Print Resolution.
You can adjust the canvas size of your printed image by changing the resolution setting, without having to change the overall pixel dimensions of the image.
That’s about all there is to know about changing your canvas size in GIMP. Your images should work for you, not against you – and now you can control the canvas size to fit your creative vision.
Do you have a question about canvas size that isn’t answered by this post? Did I leave out your favorite method of changing canvas size in GIMP? Let us know in the comments below!
About Thomas Boldt
Ella
Thank you for these tutorials. Sometimes the simplest thing, like resizing a canvas, isn’t as intuitive as it could be. This to-the-point explanation was exactly what I needed. Thanks again!
kelly
I’ve been trying to crop a picture I have of my little ones feet and handprints to make a collage round a poem 8n libre office.
I managed to crop the handprints without changing their size, and set alpha then exported to PNG but when I open the image it has a big white background the size of A4.
I’ve tried cropping to selection/content but then this changes my handprint size. I’m new to all this and would love some advice on what I’m doing wrong!
Thomas Boldt
Hi Kelly, I’m not too familiar with LibreOffice, so I’m not sure that I’ll be able to help. It sounds like the issue is with how LibreOffice is interpreting the PNG you exported from GIMP, but it’s hard to say for sure. What happens if you open the PNG using a basic image viewer app? Does it still have the huge A4-sized white background?
If not, then the problem is with how LibreOffice is reading the PNG, and I’m not sure what to suggest.
If the PNG always has that giant background, then there’s a problem with the way you’re cropping and exporting the image. This tutorial about cropping is probably more helpful! https://thegimptutorials.com/how-to-crop-image/