Free tool
Social preview checker
Fetch a page the way iMessage, Slack, WhatsApp, X and Facebook do, check its Open Graph tags and image, and see a mock of every preview.
What this checks
- The page as each app's crawler gets it, using that crawler's own User-Agent, following redirects the way they do.
og:title,og:description,og:imageandtwitter:card, and the fallbacks each app uses when one is missing.- The image itself: that it loads, its type, its pixel size and its file size, from the first 64 KB.
- The usual failures: no image, an image that's too small or too big, an http image URL, a redirect to a page without tags, and a site that blocks a crawler.
Questions
- Why does my link show no image in WhatsApp?
- The usual causes are a missing og:image, an image URL over http, or a large file: WhatsApp often skips images of several hundred KB. Use a 1200×630 JPEG or PNG under 300 KB on an absolute https URL.
- I fixed the tags. Why does the old preview still show?
- Every app caches previews. Facebook's Sharing Debugger can re-scrape a URL, Slack and X refresh on their own after a while, and iMessage builds the preview on the sender's device when the message is written, so new messages pick up the change.
- Why does the preview work for Slack but not for X?
- Some firewalls and bot rules let one crawler through and block another, and some sites serve different HTML per User-Agent. This checker fetches the page with each app's own User-Agent so you can see the difference.
- What size should og:image be?
- 1200×630 pixels (1.91:1) works as a large card everywhere. Facebook needs at least 200×200 and X's large card at least 300×157; X's limit is 5 MB and Facebook's 8 MB.
Links that unfurl and open the app
Every DeepLinkNow link serves Open Graph tags from your app's settings, on every path, so links unfurl with no setup and open your app when tapped.