How to Resize an Image in Gimp

If you need to edit an image’s size, whether it’s the dimensions or the file size itself, GIMP is the perfect software to do this. Not only is this photo editing program free, but it can be installed on devices running Windows, macOS, and GNU/Linux. You can use it to change an image’s dimensions and file size, as well as to crop, rotate, and flip an image.

In this guide, we will show you how to resize image dimensions and file size in GIMP without reducing its quality or resolution. In addition, we will go through the process of resizing a layer, canvas, and selection in GIMP.

How to Resize Image Dimensions in GIMP

Knowing how to resize an image can be very handy when you need to post the same image on various social media outlets. Different platforms have different requirements for their posts’ aspect ratios and dimensions. The trick is to change the dimensions of the photo without cropping it, as this might result in the image losing potentially important elements.

Fortunately, you can use GIMP to resize the dimensions of an image, and it will only take you a few moments. It doesn’t matter which OS you use; this process is the same on all of them. First, you need to download the software and install it on your computer or laptop. After you open GIMP, this is what you need to do next:

1. Click on the “File” tab in the upper-left corner of the window.
   
2. Go to the “Open” option and select the image that you want to resize.
   
3. Click on it and select “Open” in the new window.
   Note: You’ll be able to see the current image dimensions in the second half of the title tab (e.g., 800 x 1200 – GIMP).
   
4. Select the “Image” tab on the top menu.
   
5. Choose “Scale Image…” from the drop-down menu. This will open the “Scale Image” dialogue.
   
6. Under “Image Size,” change the width and height of the image manually.
   
   • You can also change the type of value by clicking on the downward arrow next to the “px” tab. It’s possible to change the value to percentages, millimeters, centimeters, and more. If you don’t need to, we recommend that you just leave it at pixels.
7. Click on the “Scale” button when you’re done.
   

If there are no further changes you want to apply to this image, you can save it. You can do that by clicking on the “File” tab again, and choosing “Export As….” Decide which folder you want to save the edited image in and go to the “Export” button.

How to Resize Image Dimensions With a Mouse Drag in GIMP

There’s an even easier and faster way to resize image dimensions in GIMP, and that’s by dragging it with your mouse. This is how it’s done:

1. Launch GIMP and open a new image.
   
2. Click on the “Unified Transform Tool” icon on the left sidebar. It’s the sixth icon in the first line.
   
3. Under “Constrain (Shift),” make sure the “Scale” option is checked.
   
4. Under “From Pivot,” check the “Scale” box.
   
5. Click on one of the four squares on each side of the photo to resize it.
   
6. To make the image bigger, drag the square towards the edge of the window.
   
7. To make the image smaller, drag the square towards the center of the window.
   

You’ll be able to see the pixel percentage on the bottom left side of the window. If you want to resize it in a different way, go to the “Reset” button on the “Unified Transform” window. When you’re done, save the changes and export the image to your computer.

How to Resize an Image’s File Size in GIMP

GIMP also gives you an option to change an image’s file size. This can be especially handy when you want to send someone an image, but it’s too large to fit in the attachment section. This is how it’s done:

1. Launch GIMP and import an image.
   
2. Make all the necessary changes to the image.
3. Select “File” in the upper-left corner of the window.
   
4. Choose “Export As…”
   
5. Click on the “Select File Type (By Extension)” option.
   
6. Select “JPEG image” and click on the “Export” button.
   
7. Choose the quality of the image, which will also determine its size.
   
8. Go to “Export” again.
   

For any image you edit, the smaller the file size, the lower the image quality. You can change an image’s file size only if you export it in JPEG format.

How to Resize a Layer in GIMP

You can also add layers on top of your image in GIMP. To choose the right dimensions of a layer, follow the steps below:

1. Select “Layer” on the top menu.
   
2. Click on “New Layer” on the drop-down menu.
   
3. Choose the width and height of the layer.
   
4. Click on the “OK” button.
   

If you want to resize the dimensions of an existing layer, do the following:

1. Right-click on the layer and choose “Layer.”
   
2. Proceed to “Scale Layer.”
   
3. Change the width and height of the layer.
   
4. Click on the “Scale” button.
   

That’s all there is to it. You can add as many layers as you want to your project.

How to Resize Without Losing Quality in GIMP

As mentioned before, you can change an image’s file size. However, if you reduce the file size too much, you could risk losing the image quality. There are certain things you can do to retain the image’s original quality. Follow the steps below to do so:

1. Open GIMP and import a new image.
   
2. Go to the “Image” tab and select “Scale Image….”
   
3. Change the width and height of the image.
   
4. Next to “Interpolation,” select “Cubic.” If you can see a “Sinc (lanczos3)” option, you can select this as well.
   
5. Select “Scale.”
   
6. Go to “File,” and then “Export As….”
   
7. Select the file type and choose “JPEG file” from the drop-down menu.
   
8. Make sure the image quality is set to 100%.
   
9. Choose “Export.”
   

How to Resize the Canvas to an Image in GIMP

In GIMP, a canvas refers to the visible area of the image. The canvas and layers are the same sizes by default. To resize a canvas in GIMP, this is what you need to do:

1. Click on the “Image” tab on the top menu.
   
2. Select “Canvas Size” on the drop-down menu.
   
3. Change the width and height of the canvas.
   
4. Choose the “Resize” button.
   

If you want, you can also resize the layers to fit the canvas in the same place. Just go to “Resize Layers” and choose “All Layers” from the menu.

How to Resize a Selection in GIMP

To draw a selection in GIMP, you can use a variety of tools – the free select tool, the rectangle select tool, the ellipse select tool, fuzzy select tool, the foreground select tool, the paths tool, select by color tool, and more. This is what you need to do:

1. Make a selection of your image. You can do this by clicking on any of the selection tools on the left sidebar.
   
2. Go to “Tools” on the top menu and proceed to “Transform Tools.”
   
3. Select “Scale.”
   
4. Change the width and height.
   
5. Click on the “Scale” button.
   

Resize All Your Images With GIMP

GIMP might seem complicated to use at first, but once you get the hang of it, you’ll use all its features to your advantage. You can use GIMP to change an image’s dimensions and file size. You can also use it to resize a layer, canvas, and selection. With lots of creative options, you’ll be able to design amazing images.

Have you ever used GIMP to resize an image before? Which method did you use to do this? Let us know in the comments section below.