Bluesky Image Size

The recommended image dimensions for Bluesky profiles, banners, and posts in 2026

Bluesky has quickly grown from a small invite-only experiment into a serious social platform with millions of users. Built on the open AT Protocol, it feels familiar if you've used Twitter/X - short text posts, image sharing, and a chronological feed. But getting your images sized correctly on Bluesky has its own quirks. The platform won't crop your uploads, which is both a blessing and a potential headache if your dimensions are off. Here's everything you need to know about Bluesky image sizes so your profile and posts look sharp on every device.

Bluesky Profile Picture Size

Your Bluesky profile picture should be 400 x 400 pixels with a 1:1 aspect ratio. The platform displays your avatar as a circle throughout the app - in your profile, in reply threads, and in other people's feeds when they see your posts. Uploading a square image at the full 400 x 400 resolution gives you the clearest result.

Since the circular crop cuts the corners off your square upload, keep important details like your face or logo centered. Bluesky accepts PNG and JPG formats for profile pictures with a maximum file size of 1 MB. If your image is larger than 400 x 400, the platform scales it down automatically.

One thing to watch for: your avatar appears at different sizes depending on context. It's smallest in feed posts (about 40 pixels across) and largest on your profile page. A high-contrast image with simple shapes reads well at every size. Avoid tiny text or intricate patterns that disappear when the avatar shrinks.

Bluesky Banner Size

The Bluesky profile banner should be 1500 x 500 pixels with a 3:1 aspect ratio. This wide strip sits at the top of your profile page, giving you a chance to set the visual tone for anyone visiting your account. The banner takes up a good chunk of the screen, so it's worth getting right.

On mobile devices, the banner gets cropped slightly tighter on the sides, and your profile picture overlaps the bottom-left corner. Keep critical elements like text or faces in the center of the image rather than the edges. A simple background pattern, gradient, or wide landscape photo tends to work better than something text-heavy that might get cut off.

Bluesky limits banner uploads to 1 MB, which is tighter than most other platforms. If your image exceeds that, compress it before uploading. PNG files are usually larger than JPGs at the same quality, so switching to JPG is often the easiest way to get under the limit without visible quality loss.

Bluesky Post Image Size

Bluesky supports several image formats in posts, and the good news is the platform doesn't crop your images regardless of their aspect ratio. The recommended landscape post size is 1200 x 675 pixels (16:9) or 1200 x 627 pixels (1.91:1), which fills the feed width nicely on both desktop and mobile. For square posts, use 1080 x 1080 pixels, and for portrait-oriented images, 1080 x 1350 pixels (4:5) works well.

You can attach up to 4 images per post. When you add multiple images, Bluesky arranges them in a grid - two images sit side by side, three create a layout with one large and two small, and four appear in a 2x2 grid. Each image has a max file size of 2 MB, and the platform accepts PNG, JPG, and WebP formats. The CDN supports images up to 4000 x 4000 pixels maximum resolution.

Since Bluesky doesn't force-crop your uploads, images appear exactly as you create them. This is different from platforms like Instagram or Facebook that often trim images to fit their feed layouts. The trade-off is that oddly proportioned images (very tall or very wide) can look awkward in the feed even though they're technically supported.

Bluesky Link Preview Image Size

When you share a link on Bluesky, the platform pulls the Open Graph image from the page and displays it as a card preview below your post text. The ideal size for these link preview images is 1200 x 630 pixels with a 1.91:1 aspect ratio. You can also manually replace the auto-generated thumbnail with a custom image before posting.

If your website's OG image is a different size, Bluesky will still display it, but it might not fill the card properly or could appear letterboxed. The 1200 x 630 dimension is the same ratio that works well on LinkedIn and Facebook link previews too, so one image covers multiple platforms. The max file size for link card images is 1 MB.

For the best results, make sure your website has proper Open Graph meta tags set up. The title, description, and image all get pulled into the link card. Text on the image should be large enough to read at small sizes, since the preview card isn't very tall in the feed.

Bluesky Custom Feed & List Images

Bluesky lets users create custom feeds and lists, and each one can have its own avatar image. Feed and list avatars follow the same sizing as profile pictures - 400 x 400 pixels in a 1:1 square that gets displayed as a circle. These show up in the feed discovery section and in sidebar navigation.

Since custom feeds are a big part of the Bluesky experience (replacing algorithmic timelines with community-curated ones), having a distinctive feed avatar helps yours stand out. Use a bold, simple icon or graphic that's recognizable at small sizes. The file size limit is 1 MB, same as profile pictures. Note that feed icons display as rounded squares (squircles) rather than circles, so corner content is slightly more visible.

Bluesky Video Dimensions

Bluesky added video support in 2024 and expanded the limit in March 2025. Videos can now be up to 3 minutes long with a maximum file size of 100 MB. The platform supports common aspect ratios including 16:9 landscape (1920 x 1080), 9:16 portrait (1080 x 1920), and 1:1 square (1080 x 1080). Aspect ratios must be between 1:3 and 3:1.

For the best playback quality, upload in MP4 format with H.264 video and AAC audio encoding. Bluesky also accepts MOV, WebM, and MPEG formats, though MP4 is the most reliable. Videos play inline in the feed with a tap-to-unmute pattern similar to other platforms. Note that Bluesky limits users to 25 video uploads or 10 GB of video bandwidth per day to deter spam. If you're repurposing video content from TikTok or YouTube Shorts, the 9:16 portrait format works natively on Bluesky too. One thing to know: Bluesky does not support native GIF uploads - animated .gif files upload as static images. To post animations, use the built-in Tenor GIF integration or upload a short looping MP4 through the video uploader.