# Bluesky Aspect Ratios & Image Sizes in 2026: Posts, Video, Profile

> Every Bluesky aspect ratio and image size for 2026: avatar (1:1), banner (3:1), post images, and video specs, plus the file limits that keep your visuals from getting cropped.

**Source:** https://posteverywhere.ai/blog/bluesky-aspect-ratios
**Author:** Jamie Partridge
**Published:** 2026-05-29

---

> **What aspect ratios does Bluesky use in 2026?**
>
> Bluesky uses **1:1 (400×400 px)** for the avatar and **3:1 (1500×500 px)** for the banner. Post images work best at **1:1 (1080×1080 px)**, **1.91:1 landscape (~1200×627 px)**, or **4:5 portrait (~627×1200 px)**, capped around 1000px on the longest side. Video is **16:9, 9:16, or 1:1**, up to 3 minutes and 100MB.

**The right Bluesky image sizes in 2026 are simple: 400×400 for your avatar, 1500×500 for your banner, and roughly 1000px on the longest side for post images.** Get them right and your visuals look crisp and uncropped; get them wrong and Bluesky's compression or feed cropping can leave you with a blurry avatar or a banner with the key part cut off.

This is your quick-reference guide to every Bluesky aspect ratio and size: profile, posts, and video, plus the file limits that matter. Because [strong visuals earn faster early engagement](/blog/how-to-go-viral-on-bluesky), and early engagement is what pushes a post into the Discover feed, getting these ratios right is a small detail that quietly helps your reach on a [fast-growing network](https://backlinko.com/bluesky-statistics). Bookmark it for whenever you're sizing an image for Bluesky.

## Bluesky Aspect Ratios at a Glance

| Asset | Dimensions | Aspect ratio | Notes |
|-------|-----------|--------------|-------|
| **Avatar** | 400×400 px | 1:1 | Displayed as a circle |
| **Banner** | 1500×500 px | 3:1 | Sides crop on mobile; center key elements |
| **Post image (square)** | 1080×1080 px | 1:1 | Safest all-rounder |
| **Post image (landscape)** | ~1200×627 px | ~1.91:1 | Good for link-style visuals |
| **Post image (portrait)** | ~627×1200 px | ~4:5 | Takes more vertical feed space |
| **Video** | 1920×1080 / 1080×1920 / 1080×1080 | 16:9 / 9:16 / 1:1 | Up to 3 min, 100MB |

These match the practical specs documented across current [Bluesky media guides](https://socialbee.com/blog/bluesky-content-guidelines/). When in doubt, square (1:1) is the safest choice, it displays cleanly everywhere and [cross-posts neatly to X and Threads](/blog/how-to-post-the-same-thing-to-x-and-bluesky).

## Post Image Aspect Ratios

Post images are the ones you'll size most often. Bluesky caps images at roughly **1000px on the longest side** and compresses larger files, a constraint of how the open [AT Protocol](https://atproto.com/) handles media, so there's little point uploading enormous images. You can attach **up to 4 images per post**.

Three aspect ratios cover almost every post:

- **1:1 square (1080×1080)**, the safest, displays cleanly in-feed
- **Landscape (~1200×627, ~1.91:1)**, good for graphics and link-style cards
- **Portrait (~627×1200, ~4:5)**, claims more vertical space in the feed, which can boost attention

If you reuse images across networks, mind the differences, our [social media aspect ratios reference](/blog/social-media-aspect-ratios) shows how each platform crops the same image, which matters when you [cross-post to X and Bluesky](/blog/how-to-post-the-same-thing-to-x-and-bluesky).

## Bluesky Video

Bluesky supports video up to **3 minutes** and **100MB**. Stick to standard aspect ratios, **16:9 (1920×1080)** for landscape, **9:16 (1080×1920)** for vertical, or **1:1 (1080×1080)** for square. Add captions for accessibility and for the silent autoplay most users scroll with.

## Profile Avatar

Your avatar should be **400×400 pixels (1:1)**. Bluesky displays it as a circle throughout the app, so keep your face or logo centred and away from the corners, which get clipped by the circular crop. A clean, high-contrast avatar reads better at the small sizes it appears in feeds and replies.

## Profile Banner

Your banner should be **1500×500 pixels (3:1)**, the same proportions as a classic header image. Two things to watch: on mobile, the banner [crops slightly tighter on the sides](https://hypefury.com/bluesky/bluesky-image-sizes/), and your avatar overlaps the bottom-left corner. Keep text and faces in the centre, away from the edges and that lower-left zone, so nothing important gets hidden.

## Bluesky File Sizes, Formats & Upload Limits

Aspect ratios decide the shape; file size and format decide how crisp the result stays after Bluesky's compression. Here are the limits that matter across every asset:

| Asset | Formats | File size | Other limits |
|-------|---------|-----------|--------------|
| **Post image** | JPG, PNG, GIF, WebP | ~1MB each (larger files are compressed) | Up to 4 per post; capped ~1000px on the longest side |
| **Avatar** | PNG, JPG | ~1MB | Circular crop |
| **Banner** | PNG, JPG | ~1MB | Sides crop on mobile |
| **Video** | Standard formats | Up to 100MB | Up to 3 minutes |

The practical takeaway: keep still images at or under **1MB** and lean on **WebP** where you can, since it holds quality at smaller file sizes and survives Bluesky's compression with less degradation than a heavy JPG or PNG.

## Cross-Posting Images to Bluesky

Most Bluesky accounts also post to X and Threads, and the three platforms size images differently, so a graphic that looks perfect on one can lose its edges or sharpness on another. Bluesky's roughly 1000px longest-side cap is smaller than X's 1600px feed image, which means a crisp X graphic can look soft once Bluesky compresses it, and X's wider 16:9 crop does not always sit well in Bluesky's more square-friendly feed.

The simplest fix is to size for the strictest platform and let one file travel. Keep the important content inside a centred **1:1 or 4:5 safe area**, export at or under 1MB, and the same image reads cleanly on Bluesky, X, and Threads. For a side-by-side of how each network crops the same picture, see the [social media aspect ratios reference](/blog/social-media-aspect-ratios), and for the one-click version, [cross-posting](/cross-posting) reformats every upload for each platform automatically.

## Tips for Sharp Bluesky Images

A few practices keep your Bluesky visuals looking their best:

- **Pre-size before uploading.** Export at the target dimensions so Bluesky's compression has less to do, uploading a massive file just gets it squeezed down anyway.
- **Center the important stuff.** Feed and mobile crops can trim edges, so keep faces, text, and logos toward the middle.
- **Always add alt text.** It's essential for accessibility and helps describe your image to the [feeds and search](/blog/how-the-bluesky-algorithm-works) that surface content.
- **Pair text with images.** Visual posts tend to earn faster early engagement, which helps reach, just don't let an image be an afterthought.
- **Keep files lean.** Around 1MB or under avoids heavy compression and keeps things crisp.
- **Generate visuals fast.** Our [AI image generator](/ai-image-generator) can produce on-brand graphics at the right dimensions when you need them.
- **Use WebP where you can.** WebP holds quality at smaller file sizes, so your images survive Bluesky's compression with less degradation than a heavy JPG or PNG.
- **Check it on mobile.** Most Bluesky users scroll on phones, so preview how your banner and post images crop on a small screen before you commit to them.

Nailing these specs is a small thing, but it's the difference between a feed that looks polished and one that looks careless, and on a platform where [visuals help you get noticed](/blog/how-to-get-more-bluesky-followers), polish counts, especially with [Bluesky's audience growing through 2026](https://sproutsocial.com/insights/bluesky-statistics/) and more people seeing every post.

> **Schedule pixel-perfect Bluesky posts.** PostEverywhere lets you upload, size, and schedule your Bluesky images alongside every other network. [Start your trial →](/bluesky-scheduler)

## FAQs

### What is the best Bluesky image size?

For post images, 1080×1080 (1:1 square) is the safest all-rounder and displays cleanly everywhere. Your avatar should be 400×400 and your banner 1500×500. Bluesky caps images around 1000px on the longest side and compresses larger files.

### What size is a Bluesky banner?

A Bluesky banner is 1500×500 pixels (3:1 aspect ratio). On mobile the sides crop slightly tighter, and your avatar overlaps the bottom-left corner, so keep important text and faces centered and away from those edges.

### What size should my Bluesky profile picture be?

Your Bluesky avatar should be 400×400 pixels (1:1). It's displayed as a circle throughout the app, so center your face or logo and avoid the corners, which get clipped. PNG and JPG are accepted, up to about 1MB.

### How many images can you post on Bluesky?

You can attach up to 4 images per Bluesky post. Supported formats are JPG, PNG, GIF, and WebP, each around 1MB (Bluesky compresses larger files). Images are capped at roughly 1000px on the longest side.

### What's the best aspect ratio for Bluesky posts?

Square (1:1) is the safest and displays cleanly in-feed. Portrait (around 4:5) claims more vertical space and can draw more attention, while landscape (around 1.91:1) suits graphics and link-style visuals. Match the ratio to the content.

### Can you post video on Bluesky and what are the limits?

Yes. Bluesky supports video up to 3 minutes long and 100MB, in 16:9, 9:16, or 1:1. Add captions for accessibility and for the silent autoplay most users scroll with.

## Next Steps

Bookmark these specs, size your images once, and you'll never ship a cropped banner or blurry avatar again.

- **Schedule sized-right posts**, upload and queue your Bluesky images with [PostEverywhere](/bluesky-scheduler)
- **Make visuals that spread**, see [how to go viral on Bluesky](/blog/how-to-go-viral-on-bluesky)
- **Cross-post without crop surprises**, check the [aspect ratios reference](/blog/social-media-aspect-ratios) before [posting to X and Bluesky](/blog/how-to-post-the-same-thing-to-x-and-bluesky)
- **Learn the workflow**, our guide to [scheduling Bluesky posts](/blog/how-to-schedule-bluesky)