Overview
Twitterbot is the crawler used by X (formerly Twitter) to generate Twitter Card previews when someone shares a link. It fetches your page's meta tags to build the preview card that appears in the tweet — showing an image, title, and description.
Twitter Cards come in several types: summary (small thumbnail), summary_large_image (large image banner), app, and player. The card type is controlled by the twitter:card meta tag. Most websites use summary_large_image for maximum visual impact in the timeline.
Twitterbot first checks for Twitter-specific meta tags (twitter:image, twitter:title, twitter:description), then falls back to Open Graph equivalents. This two-tier system means you can customize your preview for X separately from other platforms, or just use OG tags for everything.
User-Agent String
Twitter/X Bot identifies itself with the following user-agent string:
Twitterbot/1.0How Twitter/X Bot Handles OG Images
Twitterbot prioritizes its own twitter: meta tags but falls back to standard OG tags. You can use either or both.
Meta Tags Read
twitter:cardtwitter:imagetwitter:image:alttwitter:titletwitter:descriptiontwitter:sitetwitter:creatorog:imageog:titleog:description| Preferred Size | 1200 × 630 |
| Minimum Size | 144 × 144 (summary), 300 × 157 (summary_large_image) |
| Max File Size | 5 MB |
| Cache Duration | ~7 days |
Caching Behavior
X caches card data aggressively. The Card Validator no longer shows a visual preview, though it still supports metadata validation and cache clearing. Appending a query parameter to your URL can also force a fresh fetch.
Fallback Behavior
If no twitter:image or og:image is found, X will not show an image in the card. The link appears as a text-only card with title and description.
Things to Know
- The twitter:card meta tag is required for any card to render. Without it, X falls back to a basic link.
- Images are cropped to a 2:1 aspect ratio for summary_large_image cards. Design with center-weighted content.
- GIF images are supported but only the first frame is displayed as a static image.
- X does not support og:image:width/height — it always fetches the full image to determine dimensions.
robots.txt
Twitterbot strictly respects robots.txt. If you block it, no Twitter Card will be generated — the link appears as a plain URL with no preview. This is a common cause of missing previews.
User-agent: Twitterbot
Allow: /How to Test
X's Card Validator no longer shows a visual preview but still validates metadata and clears the cache. The most reliable way to see the actual card is to share your link in a tweet (you can use a private/protected account).
- Use a private account to test links without publishing them publicly.
- Check your server logs for requests with the Twitterbot/1.0 user-agent to confirm X is fetching your page.
- If your card isn't showing, verify that your robots.txt allows Twitterbot — this is the most common issue.
You can also use the MyOG OG Preview tool to check how your OG tags are configured before testing with Twitter/X Bot.
FAQ
What is Twitterbot?
Twitterbot is X (formerly Twitter)'s web crawler that fetches meta tags from URLs shared on the platform. It reads twitter: and og: meta tags to generate Twitter Card previews — the image, title, and description shown in a tweet when a link is shared.
Why isn't my Twitter Card showing an image?
The most common causes: missing twitter:card meta tag (it's required), robots.txt blocking Twitterbot, image URL returning an error, or image exceeding the 5 MB size limit. Check your robots.txt first, then verify your meta tags are present using your browser's developer tools.
What size should Twitter Card images be?
For summary_large_image cards (the most common type), use 1200 × 628 pixels. Images are cropped to a 2:1 ratio, so keep important content centered. For summary cards, the minimum is 144 × 144 pixels. Maximum file size is 5 MB.
Related Bots
Check what crawlers see
Paste your URL to test OG tags, image fetches, crawler access, and the preview card before you share it.
Already have an account?