This article explains how to change your Discord avatar using a computer.
Steps
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Step 1. Visit
You can use any browser, such as Safari or Chrome, to access Discord.
If you are not already logged in, click on "Log in" in the upper right corner of the screen, then enter the required information to continue
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Step 2. Click on the gear button
It's at the bottom of the screen, under your friends list. This will open the user settings.
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Step 3. Click Edit
This option is next to your username and current profile photo.
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Step 4. Click on the current image
A window will appear allowing you to browse the files saved on your computer.
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Step 5. Select the image you want to use and click Open
The file will then be uploaded to Discord.
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Step 6. Click Save
This option is located at the bottom of the window titled "My Account". At this point you should see your new avatar instead of the previous one.