Bluesky image size, in short: post images can be up to 2 MB each and up to 4 per standard post; 1080×1350 (4:5) or 1080×1080 (1:1) work best in the feed. The profile picture is a square JPEG or PNG up to 1 MB (use 1000×1000); the banner is a 3:1 JPEG or PNG up to 1 MB (use 1500×500). Link cards use 1200×630, and the app accepts MP4 videos up to 10 minutes.
More on this topic: Social media image sizes, every guide in one place.
Bluesky doesn't publish a size chart in a help center. The firm numbers come from two public sources the company maintains: the AT Protocol lexicons, which set the hard limits every upload must meet, and the open-source Bluesky app, which shows how the app crops and resizes what you upload. This guide uses those, marks which sizes are our recommendation, and shows how to resize product photos for the feed, your profile and link previews.
- Post images: up to 2 MB each (it was 1 MB until recently); the app scales them so the longest side is at most 4000 px.
- Best feed size: 1080×1350 (4:5) or 1080×1080 (1:1), our recommendation.
- Images per post: 4 in a standard post; newer app versions add a gallery of up to 10.
- Profile picture: square, JPEG or PNG, 1 MB max; 1000×1000 is plenty.
- Banner: 3:1, JPEG or PNG, 1 MB max; 1500×500 or 3000×1000.
- Link card image: 1200×630 (1.91:1), 1 MB max.
What is the best image size for Bluesky posts?
1080×1350 pixels (4:5) for a single image, or 1080×1080 (1:1) for product shots and graphics. Bluesky stores each image's aspect ratio with the post so apps can show a single image at its own shape, and portrait images take up more of a phone screen than landscape ones.
| Shape | Recommended size | Best for |
|---|---|---|
| Portrait 4:5 | 1080×1350 | Single product photos, lifestyle shots |
| Square 1:1 | 1080×1080 | Product cut-outs, quote graphics, multi-image posts |
| Landscape 16:9 | 1920×1080 | Banners, screenshots, wide scenes |
| Higher detail | Up to 2000 px on the long side | Artwork, detailed products (stay under 2 MB) |
Posts with two to four images are shown as a grid, so each image is cropped in the feed preview and opens in full when tapped. For multi-image posts, use squares with the product centered so the preview crop doesn't cut it off. The free aspect ratio calculator works out any other size.
What are Bluesky's official image limits?
These come from Bluesky's published lexicons (the schema every post and profile must match) and the constants in the open-source Bluesky app.
| Limit | Value | Source |
|---|---|---|
| Image file size, posts | 2 MB per image (formerly 1 MB) | app.bsky.embed.images lexicon |
| Images per standard post | 4 | app.bsky.embed.images lexicon |
| Gallery posts | Up to 10 images in the app (schema allows 20) | app.bsky.embed.gallery lexicon and app code |
| Longest side after upload | 4000 px (the app resizes larger images) | Bluesky app image settings |
| Profile picture and banner | JPEG or PNG, 1 MB each | app.bsky.actor.profile lexicon |
| Avatar and banner resize | Up to 2000 px on the longest side | Bluesky app image settings |
| Link card image | 1 MB; shown at 1200:630 | app.bsky.embed.external lexicon and app code |
| Alt text | Up to 2,000 characters | Bluesky app |
| Post text | 300 characters | app.bsky.feed.post lexicon |
Bluesky's limits were checked in October 2026. Marketplaces change their rules, so confirm the current requirements in your seller dashboard before you upload a large batch.
Bluesky's protocol now has a gallery format for more than four images, and the open-source app caps it at 10. If your app version still stops at four images, update it or split the set across two posts.
What size is a Bluesky profile picture?
Upload a square image of at least 400×400 pixels; 1000×1000 is a good target. It must be a JPEG or PNG under 1 MB. The app crops your upload to a square, scales it down to at most 2000 px, and shows it as a circle, so keep your logo or face in the middle with space around it.
- Format: JPEG or PNG only. WebP, HEIC and GIF avatars are rejected by the profile schema.
- File size: 1 MB or less; a 1000×1000 JPEG is usually well under.
- Circle crop: the corners are hidden, so don't put text near them.
What size is the Bluesky banner?
Use a 3:1 image: 1500×500 pixels, or 3000×1000 for extra sharpness. The app crops banners to 3:1, scales them to at most 2000 px wide and compresses them to fit 1 MB, so a 3000×1000 upload ends up around 2000×667. JPEG or PNG only.
| Banner detail | Value |
|---|---|
| Shape | 3:1 (the app's crop) |
| Recommended upload | 1500×500 or 3000×1000 |
| Stored size | Up to about 2000×667 after the app resizes it |
| File | JPEG or PNG, 1 MB max |
| Covered area | Your profile picture overlaps the lower left; keep text away from that corner |
To turn a square product photo into a 3:1 banner, extend the background sideways rather than cropping the product. Crop the final image to exactly 3:1 with the free image cropper.
What size are Bluesky link previews?
1200×630 pixels. When you paste a link, Bluesky builds a card from the page's preview image and shows it at the same 1.91:1 shape used by most networks, with a 1 MB limit on the stored thumbnail. If your product page has a 1200×630 Open Graph image, it will look right on Bluesky too.
What video size does Bluesky support?
MP4 video, with the shape stored so vertical, square and landscape all display. The protocol limit is 300 MB per video, and the app allows up to 10 minutes. Use 1080×1920 for vertical clips and 1080×1080 or 1920×1080 otherwise.
The lexicon and app code set the technical ceiling. Before each video upload the app also asks Bluesky's video service whether your account can upload, so if an upload fails at a smaller size, read the app's message: it's usually an account limit, not the file.
How do you resize a product photo for Bluesky?
- Pick the shape: 4:5 for a single post image, 1:1 for multi-image posts, 3:1 for the banner.
- If the product already has space around it, crop to the shape with the free image cropper.
- If cropping would cut the product, extend the background instead.
- Export JPEG at 1080 px wide (2000 px for detailed images) and check it's under 2 MB, or 1 MB for avatars and banners. The free image compressor shrinks files in your browser.
- Add alt text describing the product; Bluesky allows up to 2,000 characters.
Bluesky's 4:5 and 1:1 sizes are the same as Instagram's, so the free Instagram image resizer works for Bluesky too. AiArter's AI image extender extends the background to 4:5, 9:16 or 16:9 for 8 credits per size so the product isn't cropped.
Extend a square product photo to 1080×1350 for Bluesky and Instagram without cropping the product.
Extend to 4:57 days free · 50 credits · No credit cardHow do Bluesky sizes compare with Threads and X?
| Bluesky | Threads | X | |
|---|---|---|---|
| Best single image | 1080×1350 (4:5) | 1080×1350 (4:5) | 1080×1350 or 1600×900 |
| Max image file | 2 MB | 8 MB | 5 MB |
| Images per post | 4 (gallery up to 10) | Up to 20 in a carousel | 4 |
| Banner | 3:1, 1500×500 | None | 3:1, 1500×500 |
Full details: Threads image size and Twitter (X) image size. If you post the same image to Instagram, see Instagram post size.
Frequently asked questions
What size should Bluesky images be?
1080×1350 (4:5) or 1080×1080 (1:1), JPEG or PNG, under 2 MB each.
What is the maximum image size on Bluesky?
2 MB per post image. The app scales images so the longest side is at most 4000 px. Profile pictures and banners are limited to 1 MB.
How many images can you post on Bluesky?
Four in a standard post. Newer versions of the app add a gallery format of up to 10 images.
What size is a Bluesky banner?
3:1. Upload 1500×500 or 3000×1000, JPEG or PNG, under 1 MB.
What size is a Bluesky profile picture?
A square of at least 400×400; 1000×1000 is ideal. JPEG or PNG, under 1 MB, shown as a circle.
Does Bluesky crop images?
A single image keeps its shape. Posts with several images show cropped previews in a grid, and avatars and banners are cropped to 1:1 and 3:1.
Can I upload a PNG with a transparent background to Bluesky?
Posts accept any image type, but the background may show as white or black depending on the app's theme. Use a solid background for product photos.
How long can a Bluesky video be?
Up to 10 minutes in the app, MP4, with a 300 MB protocol limit.
Turn one product photo into feed posts, a 3:1 banner and Story sizes, with AI filling extra space instead of cropping the product.
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