# Bluesky Open Graph

## Test and debug your Open Graph tags for Bluesky

### Bluesky Specs

|     |     |
| --- | --- |
| Image size | 1200x627px |
| Aspect ratio | 1.91:1 |
| Max file size | 5 MB |
| Formats | image/jpeg, image/png, image/webp, image/gif |
| User-Agent | Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Bluesky Cardyb/1.1; +mailto:support@bsky.app) Chrome/W.X.Y.Z Safari/537.36 |

[Official docs](https://docs.bsky.app/docs/advanced-guides/posts#website-card-embeds)

Bluesky is built on the AT Protocol, a decentralized social networking protocol. Link card data is fetched by a service called CardyB and then baked permanently into the post record, making Bluesky’s caching model fundamentally different from every other platform.

This guide covers how CardyB crawls your pages, which tags Bluesky reads, image compression requirements, the immutable caching model, and the most common issues that prevent cards from displaying correctly.

## What links look like on Bluesky

### The difference Open Graph tags make when sharing a link.

#### Without Open Graph

This site doesn't have Open Graph

#### With Open Graph

Sites with Open Graph look like this

### Debug Bluesky Open Graph tags

Enter your site's URL to see how it looks on Bluesky.