GIMP allows you to create your own custom palettes from a variety of sources – whether that’s purely through experimenting with the eye-dropper tool and the “Change Foreground/Background Color” dialogue (i.e. the color wheel), or by using the colors in an image composition and some of GIMP’s built-in tools to extract specific colors to form a palette (as I demonstrate in this GIMP tutorial on how to create custom palettes).
However, what if you had a palette that someone else created in GIMP that you wanted to upload into your GIMP? How would you accomplish such a task? Also, how can you export your own palettes out of GIMP for other people to upload? In this article, I show you how to install custom palettes in GIMP using two different methods. The first method shows you how to add .GPL palette files to GIMP. The second shows you how to create a readable palette file (exported from GIMP) that you can then import into GIMP (much like a .GPL file – though this method allows non-coders to create and upload palette files without a plugin). Let’s dive in!
Method 1: Using .GPL Files
1. Locate the Palettes Section of GIMP
The reason I am starting with this step is that it helps to know how to locate palette files both within GIMP and on your computer. This helps you understand what types of files palettes are contained in, and in which folder they are typically found.
You can find your palettes by going to Windows>Dockable Dialogues>Palettes (denoted by the red arrow in the photo above). This will open up all of the palettes you have created in GIMP or that came with GIMP by default. Again, if you are looking for information on how to create a palette, I recommend checking out my video tutorial on my YouTube channel.
Once you are in the Palettes tab (denoted by the green arrow in the photo above), you can choose a palette you’d like to work with. For this tutorial, we are going to use the “Isometric Building Color” palette (this palette was created for my Create a 3D Isometric Building with GIMP 2.10 | Speed Art tutorial on my channel).
2. Locate the Palette File You Are Working With
Right click on the Isometric Building Color palette and go to “Show in File Manager” (denoted by the red arrow in the image above). This will take you to the folder on your computer where all of your palettes are stored.
You will notice that all of the files in this folder are .GPL files (shown above) – GIMP’s native filetype for palettes.
You can also find your Palettes folder by going to Edit>Preferences>Folders>Palettes. The address displayed here shows the folder hierarchy on your computer that ultimately leads to the folder where your palettes are located (denoted by the red arrow in the photo above).
You can copy this address and paste it into your File Manager (in Windows) at the top.
3. Copy the Palette File You Want to Import Into GIMP Into This Folder
Now that you know where all of the palette files are located, you can simply copy and paste any .GPL file into this folder to upload a new palette. So, for example, if you downloaded a .GPL file from a website into your Downloads folder on your computer, you can copy the file from your downloads folder and paste it here into this palette folder.
Once you’ve copied your new .GPL palette file into your folder, be sure to go back into GIMP and click the “Refresh Palettes” icon (the green arrow) at the bottom of the Palettes dockable dialogue.
That’s it. Seriously – it’s that easy!
Method 2: Using a Palette File Exported From GIMP (Usually a .CSS or .TXT File)
This section is for non-coders/non-developers – so don’t be scared by the filenames mentioned in the title. However, that being said, you will need to tweak some code to make this work (I’ll be walking you through that portion).
1. Export Your Palette File From GIMP
The first thing you’ll need to do is export your palette file out of GIMP. You can skip this step if someone has already given you a working .TXT file for you to upload. You can skip all the way down to Step 4 to see how to import your working palette file.
Otherwise, go to your Palettes tab and right click on the palette you want to export. Go down to “Export As” and select “CSS Stylesheet” (demonstrated in the image above – and denoted by the red arrow). You won’t need any kind of code reader to open and work on this file. You will simply need a basic text editor, which comes free on every computer (usually).
Next, choose the location on your computer where you want to export the file using the dropdown (I went with my Desktop), then rename the file to whatever you want it to be called (make sure you don’t have any spaces in the name – I used the “_” character in place of a space. You also want to make sure the filename ends in .css). Click OK to save the file, which will export your palette to a .CSS file. This file will contain code – but don’t be alarmed, it’s fairly simple code.
2. Make Some Minor Tweaks to Your CSS File So GIMP Can Read It
Pull up your file manager on your computer (or Finder Window on a MAC) where you exported your file (you’ll see here that I am in my Desktop Folder). Find the CSS file and double click on it. This should open the file into your text editor (if it doesn’t, right click on it and choose “Open With.” Select “Notepad” as the program you’d like to open it with).
All of the code for the palette will be displayed on a single line (the image above has the title on the first line and code on the second line – this is for the step in the next paragraph). Unfortunately, GIMP can’t read the palette in this format (which begs the question: why did the GIMP team choose to export to a format that its own program can’t read?), so we’ll have to tweak it a bit to make it work. Luckily for you, I’ve figured this part out ahead of time.
You’ll first want to click your mouse directly after the second forward slash character (“/” – I highlighted it in blue in the photo above) and press the enter key. This will put the code for all of your palette colors on the second line (as displayed in the image above), and will leave the title of the document alone on the first line (/* Generated with GIMP Palette Export */).
Just so you understand what is going on here – GIMP has exported each palette (15 in total in my case) as a piece of code. The part that says “Untitled” is the name of the individual palette color (none of these palette colors had custom names when I exported the palette – hence why it says “.Untitled” for each one). Next, inside of a pair of brackets you have the code for each color as it corresponds to its RGB value (hence why it says color: rgb(XXX, XXX, XXX). When it comes to RGB values expressed as a code, the first 3 numbers correspond to red, the second set of 3 numbers corresponds to green, and the third set of 3 numbers corresponds to blue.
What we are going to do is strip away all of this code so that the only thing left are the individual RGB values for each color in the palette. Plus, each of these RGB values will be on its own line instead of sharing a line with the other colors.
To start this process, put each color on its own line by clicking your mouse directly after the closing bracket character (“}”) and pressing the enter key (shown in the image above).
Once you have done that, delete everything in each line EXCEPT for the RGB numerical values (you can leave the commas).
Your document should now only contain the title at the top, followed by 15 rows – each with 3 sets of numbers.
Next, you’ll need to replace the title of your document (the very first line) with this title (as I’ve done in the photo above):
Name: Enter a Title for Your Palette Here
The reason for this is that GIMP needs to be able to properly read the document as a palette file. The above title is the format it looks for. You can replace the “Name” field with whatever name you would like to give your palettes. However, everything else needs to remain the same. Additionally, you need to make sure that each part of the title is on its own line (there should be 4 lines total when you are finished).
3. Name Your Colors
Now that we have a proper title on our document, along with each RGB color code on its own line, we can now name each color so that they will be labeled when we import them into GIMP. To do this, click at the end of the last number in each number set and hit the Tab key on your keyboard (this will add a big space after the last numerical value – I pointed to the first entry I did with the red arrow in the photo above). Now, type whatever name you want for this color (it helps to know what that color actually is. I went back and double clicked on my palette within GIMP so I could see what each color was – as you can see on the right side of the photo).
Once you have named your color, click on the last number of the second row of RGB values and continue the process above. Repeat this for all 15 colors in your color palette (or however many you have).
4. Save and Import Your Palette
Now that you have everything properly configured in your Palette file, go to File>Save (or hit Ctrl+s) to save the file. You can name the file whatever you want – just ensure you save it as a .TXT file. Choose the destination where you want to save the document on your computer and click save.
Next, navigate back over to the Palette tab in GIMP. Right click anywhere within the list of Palettes and go to “Import Palette” (shown in the photo above).
In the dialogue window that pops up, you’ll want to check the “Palette File” option (red arrow in the image above). Then, click the box labeled “(None)” with the folder icon (green arrow in the image above) to select the Palette file from your computer.
I navigated to my Desktop folder and clicked on the “iso__building_palette.txt” file I created (red arrow in the photo above). Click Open once you have selected your file. If no error message pops up at this point, it means you have done everything right. If you do get an error message, you will need to go back to your .TXT document and figure out where you went wrong.
You should see your Palette colors in the “Preview” box (denoted by the red arrow in the image above). If everything looks good, click the “Import” button.
You should now see your Palette among the list of palettes in GIMP (it will have the same name as your .TXT document). If you want to edit any of the attributes of the Palette, including the name, right click on your palette and go to “Edit Palette” (red arrow in the photo above). Otherwise, you can double click on your palette to view or use all of the different colors!
If you liked this tutorial, you can also check out any of my GIMP Video Tutorials on my YouTube channel or on the Tutorials page on my website, or you can read any of our GIMP How-To Articles!