Creating a Transparent GIF in the GIMP

This tutorials shows how to create a transparent GIF in GIMP 2.x. It assumes you understand the GIMP's basic functionality, such as creating an image, using the selection tool, and saving an image.

The process of creating a transparent GIF involves adding an alpha channel to an image, selecting the areas you want to make transparent, and cutting out those areas.

1. Create or open an image.

   You'll get better results if the areas that you want to cut are aliased.

2. Right-click the image and select Layer > Transparency > Add Alpha Channel.

   GIMP adds the alpha channel without any indication of doing so. The image won't look any different but the alpha channel really is there.

3. Select the area you want to make transparent, such as a contiguous region, a single color, or a hand-drawn region (following figure).

   

   Selected Area in Image

4. Cut the selection.

   The GIMP reveals the underlying alpha channel. The following image shows a white halo effect around the edges that were cut. This is due to aliasing on the original image. You can clean this up by cutting or changing the color of individual pixels.

   

   Cut Image

5. Select Image > Mode > Index.

   GIF images must use either indexed mode or grayscale mode. If you skip this step now, GIMP will prompt you to export to one of these modes when you save.

6. Save the image as a GIF file.

   Set the GIF options you want when prompted and click OK. I typically type a short comment about the image.

You now have a transparent GIF.