Social preview FAQ

Short answers for common preview metadata, crawler and cache issues.

Why does a link preview need meta tags?

Social apps read page metadata to choose a title, description and image. They usually do not render the whole page like a browser.

Which image should be first?

Use a 1200x630 wide image first. It fits Open Graph, Facebook, LinkedIn and most chat previews. X large cards also work well with 1200x628 or a close 1.91:1 wide image.

What about Pinterest?

Pinterest can use a portrait image for Rich Pins. Keep the wide Open Graph image first and add a portrait image in structured data when Pinterest matters.

Can WAF or bot protection block previews?

Yes. Real social crawlers should be allowed by verified crawler rules, not by user-agent strings alone.

Do image redirects matter?

Yes. A direct image URL is safer. Redirects can fail under bot protection, cache rules or stricter fetchers.

Why does my preview still show the old image?

Social platforms cache previews. Fix the page first, then use the platform debugger when one exists. Some services no longer provide a cache clear tool.

Why do you simulate crawlers?

The checker compares a normal fetch with crawler-like fetches. This helps spot WAF risk, but it is not the same as a verified request from a social platform IP range.

Is PreviewChecks free?

Yes, for now. It is a public tool with fair-use limits so the service stays available for everyone.

What is the API rate limit?

The public API currently allows about 20 checks per minute for the same IP and target host, with a higher per-IP ceiling across all hosts. We may lower or block abusive traffic.

Do you store checked URLs?

PreviewChecks does not store accounts or check history. Cloudflare may process standard request, security and performance data for delivery and abuse protection.

Does this replace official debuggers?

No. It gives one clear report before you use official tools. Some platforms do not provide a debugger anymore and only publish guides or recommendations.