Bluesky Sizes & Dimensions Guide

Complete specifications for all Bluesky content types. Get the exact dimensions, aspect ratios, and file requirements for Bluesky. Updated for 2026.

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Bluesky Content Specifications

Feed Image

Updated 2026

In-feed image, up to 4 per post. Bluesky re-compresses uploads, so start from a clean source.

Dimensions
1200×675 (or 1080×1080)
Aspect Ratio
16:9 or 1:1
Max Size
~1 MB per image (auto-compressed)
Format
JPG, PNG, WEBP, GIF
Images per PostUp to 4
Alt TextSupported (recommended)

Video

Updated 2026

Short in-feed video. Limits are still changing — verify current caps before relying on them.

Dimensions
1080×1920 (or 1920×1080)
Aspect Ratio
9:16 or 16:9
Max Size
~50 MB (approx — verify)
Format
MP4, MOV
Duration
60 seconds

Avatar

Updated 2026

Profile picture, displayed as a circle.

Dimensions
1000×1000
Aspect Ratio
1:1
Max Size
~1 MB (compressed)
Format
JPG, PNG

Banner

Updated 2026

Profile header image behind your avatar.

Dimensions
3000×1000
Aspect Ratio
3:1
Max Size
~1 MB (compressed)
Format
JPG, PNG

Bluesky Content Best Practices

Keep images under ~1 MB — Bluesky compresses larger files and can soften detail
Always add alt text; the Bluesky community strongly expects it for accessibility
Use a 3:1 banner (3000×1000) so it isn't cropped awkwardly on profiles
Video limits are evolving — confirm the current duration and size cap in-app

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