Bluesky Banner Size

A Bluesky profile banner is 3000 by 1000 pixels at 3:1, with the avatar overlapping its lower-left corner. Crop here with that overlap drawn on — and because X uses the same ratio at 1500 by 500, one crop serves both profiles.

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Bluesky's profile banner is a 3:1 strip at 3000 by 1000 pixels. The ratio is the same as an X header; the resolution is twice as large in each direction, which makes it noticeably sharper on a high-density screen and means a file made for X will look soft if reused directly.

The interface behaves similarly too. A circular avatar overlaps the banner's lower-left corner, and the display name and handle sit below it. The practical consequence is the same: the bottom-left of the strip is not somewhere to put anything that has to be read.

Because the ratios match, the useful workflow is one crop and two exports. Set the composition once here, take the 3000-wide file for Bluesky, and use the X header page for the 1500-wide version of the same framing.

The same crop at half the size is what X wants, so the X header resizer completes the pair.

If an upload limit gets in the way, compress rather than shrink — it keeps the resolution and removes the bytes.

Bluesky and X, side by side

Same shape, different scale. That is the whole relationship, and it is what makes a shared crop safe.

Platform	Banner size	Ratio	Avatar
Bluesky	3000 × 1000	3:1	Circle, lower left
X	1500 × 500	3:1	Circle, lower left
Discord profile	600 × 240	5:2	Circle, lower left

Why the larger file is worth exporting

3000 pixels is generous for a strip that is rendered a few hundred pixels wide on a phone, and that is precisely the point: on a display with three device pixels per CSS pixel, a 1500-pixel banner stretched across a wide window is being upscaled.

Supplying the larger file costs a few hundred kilobytes and removes the softness. If the upload is rejected for size, compress rather than shrink — reducing quality keeps the resolution, and resolution is what the density needs.

Composing around the avatar

The avatar circle overlaps the lower-left corner, and the display name sits beneath the banner rather than on it — which makes Bluesky slightly more forgiving than X, where the mobile profile card rises over the strip.

Even so, the reliable area is the upper and right portion. A gradient, a pattern or a landscape with its subject to the right survives every layout; a centred wordmark sitting low does not.

Format and what to keep

JPEG for photographic banners at this size — a 3000-pixel PNG of a photograph is several megabytes for no visible gain. PNG for flat colour or lettering. Keep the exported 3000-wide file as your master: it downscales to the X header and to any other 3:1 slot without a second crop decision.

Frequently asked questions

What size is a Bluesky banner?

3000 by 1000 pixels, a 3:1 strip. It shares its ratio with an X header but is twice the linear resolution, so a file made for X and reused directly on Bluesky is being upscaled and looks soft on a high-density display.

Can I use my X header on Bluesky?

The shape fits, but the resolution does not: 1500 by 500 stretched across a 3000-pixel slot is an upscale. The better move is to crop once at 3000 by 1000 and export the smaller X version from the same framing, which this page and the X header page do together.

Does the avatar cover part of the Bluesky banner?

Yes — a circular avatar overlaps the lower-left corner, drawn over the strip. The display name and handle sit below the banner rather than on it, which makes Bluesky a little more forgiving than X, but the lower left is still not usable for anything that has to be read.

My banner upload was rejected for being too large. What now?

Compress rather than shrink. Reducing JPEG quality keeps all 3000 pixels and removes bytes; reducing the dimensions keeps bytes and removes the sharpness you exported the large file for in the first place. The compressor takes a target size in kilobytes.

Why does 3000 pixels matter for a small strip?

Because a phone or a modern laptop draws two or three device pixels for every CSS pixel. A banner rendered 800 CSS pixels wide is really 2400 device pixels, and a 1500-pixel source cannot fill that without being enlarged. The extra resolution is what keeps it crisp.

Is my banner sent anywhere when I resize it?

No. Every step — decoding, cropping, resizing, encoding — happens in this browser tab, and this site has no upload endpoint at all. You can watch the Network panel stay empty while the export runs.

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