BlueSky Post Specifications
Complete guide to BlueSky post dimensions, character limits, and media specifications. Create engaging posts on the decentralized social network with perfect formatting. Updated for 2026.
Quick Specs
Dimensions & Resolution
Maximum 1000px on longest side
Great for landscape photos
Works well for portraits
Vertical format supported
Important Notes
BlueSky is a decentralized social media platform built on the AT Protocol. Posts (called "skeets") support up to 300 graphemes with rich media. A post can contain text only, up to 4 images, or 1 MP4 video, but images and video cannot be combined in the same post. Images are capped at 2MB each (1000px on the longest side); video is capped at 100MB. Accepted image formats: jpeg, png, gif, webp.
Optimization Tips
- ✓Keep text under 300 graphemes per post
- ✓Images max 1000px on longest side, 2MB each
- ✓Add up to 4 images per post, OR 1 MP4 video (not both)
- ✓Accepted image formats: jpeg, png, gif, webp
- ✓Use alt text for accessibility
- ✓Profile photos are 400×400px
- ✓Banner images are 1500×500px (3:1 ratio)
- ✓Bluesky-hosted accounts must verify email before their first video upload
- ✓Thread posts for longer content
Sources & Verification
Last verified: 2026-05-16
300-grapheme limit, up to 4 images (2MB each, 1000px max, jpeg/png/gif/webp) OR 1 MP4 video (100MB max). Images and video cannot be combined.
Profile & Page Dimensions
Content Limits
Text Limits
Media Limits
Features
Protocol
Built on open AT Protocol for data portability
Algorithmic
Schedule BlueSky posts at optimal times
Frequently Asked Questions
What's the character limit on BlueSky?
BlueSky posts have a 300 grapheme limit, slightly longer than Twitter's original 280. You can create threads by replying to your own posts for longer content.
How many images can I add to a BlueSky post?
Up to 4 images per post. Each image must be under 2MB and no larger than 1000 pixels on its longest side. If you attach a video instead, you cannot also attach images, the two are mutually exclusive in a single post.
Can I post video on BlueSky?
Yes. A single MP4 video up to 100MB is supported per post. Bluesky-hosted accounts must have a verified email before their first video upload. There is a per-account daily ceiling of 25 videos or 10GB combined, enforced by Bluesky.
What image formats does BlueSky accept?
jpeg, png, gif, and webp. WebP gives the best compression for staying under the 2MB per-image limit; jpeg is a good default for photos; png works well for graphics with text.
Recent Updates
Image limit raised to 2MB per image (was 1MB), webp added to accepted formats alongside jpeg/png/gif. Single MP4 video (up to 100MB) now supported as an alternative to images (images and video cannot be combined in the same post).
Migrated to evergreen URL structure. Verified all specifications current.
BlueSky maintains 300 character limit with support for up to 4 images per post
Image upload quality improved with better compression algorithms
Related Specifications
BlueSky Video
Complete guide to BlueSky video dimensions, duration limits, and technical specifications. Upload videos with perfect format for the decentralized social network. Updated for 2026.
X (Twitter) Posts
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