Facebook Open Graph
Test and debug your Open Graph tags for Facebook
Facebook Specs
| Image size | 1200x630px |
| Aspect ratio | 1.9:1 |
| Max file size | 5 MB |
| Formats | image/jpeg, image/png, image/webp, image/gif |
| User-Agent | facebookexternalhit/1.1 (+http://www.facebook.com/externalhit_uatext.php) |
Facebook invented the Open Graph protocol, so its crawler is the reference implementation for OG tags. When a URL is shared on Facebook, Messenger, or Instagram, the facebookexternalhit crawler fetches the page and builds a link preview from your meta tags.
This guide covers how Facebook’s crawler works, which tags you need, image sizing, cache behavior, and the most common issues that prevent previews from displaying correctly.
[**How Facebook Crawls Your Pages**
Understanding facebookexternalhit and how it fetches your link previews
→](/content/consumers/facebook/crawling/index.html) [**Open Graph Meta Tags for Facebook**
Which meta tags Facebook uses and the four required properties
→](/content/consumers/facebook/tags/index.html) [**Image Handling**
Image sizes, aspect ratios, and format requirements for Facebook link previews
→](/content/consumers/facebook/images/index.html) [**Caching & Invalidation**
How Facebook caches link previews and how to force a refresh
→](/content/consumers/facebook/caching/index.html) [**Common Issues**
Troubleshooting the most frequent Facebook link preview problems
→](/content/consumers/facebook/issues/index.html)
What links look like on Facebook
The difference Open Graph tags make when sharing a link.
Without Open Graph
This site doesn't have Open Graph
opengraphplus.com
Facebook Open Graph
Oh
With Open Graph
Sites with Open Graph look like this
opengraphplus.com
Facebook Open Graph
Nice!
Debug Facebook Open Graph tags
Enter your site's URL to see how it looks on Facebook.