Telegram desktop app: In the upper left corner, click the Menu icon (the one with three lines). Select “New Channel” from the drop-down menu. The optimal dimension of the avatar on Telegram is 512px by 512px, and it’s recommended to use PNG format to deliver an unpixelated avatar. Telegram Android app: Open the chats list, click the menu icon and select “New Channel.” A new window will come up. Enter your channel name and bio. (See the character limits above.) Click “Create.” 5Telegram Channel avatar size/dimensions
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