800 × 800 source

CROPPED

rendered, at the sizes YouTube actually uses

98 · channel
48 · video row
24 · comment

in a comment, which is where it is seen most

Namaste SalesforcePinned this — the governor-limit fix is at 6:40 if you came for that.

Do — the mark alone

One shape on the navy disc, with real clear space around it. It is still legible at 24px, which is the size it spends most of its life at.

Never — the wordmark
Namaste
Salesforce Namaste
Salesforce

Readable in the design tool, a grey smudge in a comment thread. The channel name is written beside the avatar everywhere it appears — putting it inside as well spends the only 24 pixels you get on information already on screen.

UPLOAD
800 × 800 PNG or JPG, square, under 4 MBSquare in, circle out. Anything in the corners is discarded — do not put a badge there and expect it back.
CLEAR SPACE
The mark occupies about the middle 60%The inner dashed ring above. A mark pushed to the edge of the crop reads as clipped even when it is not, because the eye reads the circle as a frame.
GROUND
Solid brand navy, never transparentA transparent PNG becomes a white disc on the light theme and a black one on dark — two different avatars, neither of them yours.
NO TEXT
Nothing that has to be readNot the name, not a tagline, not a subscriber milestone. 24 pixels is the design constraint, not 800.