Discord
The server banner slot does not exist until boost Level 2, which is why half the people who buy one cannot upload it.
For Discord · 960×540
Shown at the real ratio with the Vice Pier Anime design. Hover to animate. Previews are watermarked.
The server banner is the image across the top of the channel sidebar, above your channel list. It is the first thing a member sees when they switch to your server, every time they switch to it, which makes it the highest-frequency graphic in a Discord community.
It is uploaded under Server Settings, Overview, in the Server Banner block, and the slot only appears once the server reaches boost Level 2. That is two tiers up, which catches a lot of people out. Level 1 gives you an animated server icon and the invite splash; the banner comes later. Until then the still PNG in the pack is useful anyway, as a pinned image in a welcome channel or as the header of your rules embed.
Discord stores the banner at 960x540 and displays it at roughly a third of that width, cropping height on narrow windows. The practical effect is that fine detail is wasted and anything near the top or bottom edge is at risk. The layout keeps the lockup in the middle band and treats the outer rows as scene, which is why it still reads when Discord shows it at 320 pixels wide.
File size is the hard wall. Discord refuses an image over 10MB outright, and a 960x540 animation at a full colour palette gets there quickly. The animated banner is encoded at 16fps over 2.8 seconds with a 160-colour palette and lands around 7MB. That is a deliberate budget: fewer frames and a tighter palette on a scene that moves slowly looks far better than more frames at a resolution Discord is going to downscale anyway.
Discord renders it at about a third of its stored width, so saturated scenes with large shapes survive and fine detail does not.
Vice Pier rendered as anime artwork, with live motion, drifting particles and a chromed wordmark. Every format in the catalogue, still and animated.
Vice Pier rendered as grunge artwork, with live motion, drifting particles and a chromed wordmark. Every format in the catalogue, still and animated.
Vice Pier rendered as painted artwork, with live motion, drifting particles and a chromed wordmark. Every format in the catalogue, still and animated.
Vice Pier rendered as photoreal artwork, with live motion, drifting particles and a chromed wordmark. Every format in the catalogue, still and animated.
Block Party rendered as anime artwork, with live motion, drifting particles and a chromed wordmark. Every format in the catalogue, still and animated.
Block Party rendered as grunge artwork, with live motion, drifting particles and a chromed wordmark. Every format in the catalogue, still and animated.