Reddit Link Preview Checker
A link post gets a suggested title and, in most communities, a thumbnail, from the page Reddit fetches when you submit. Paste a URL to see those tags. Peekly does not draw a Reddit post.
How Reddit picks the title and thumbnail
- Title and thumbnail. Reddit does not publish a current tag list. In the old public Reddit code, the suggested title preferred og:title and fell back to the document title, and the thumbnail preferred og:image, then og:image:url, then a link rel="image_src", then a large image in the page. That is still what a submit does in practice. Set og:title, og:description, and an absolute og:image, and do not rely on the fallback.
- Why the thumbnail is missing. The old public scraper parsed the HTML it was given and did not run JavaScript. Assume the current fetch works the same way: tags that appear only after hydration are invisible. A relative image URL, an image behind a login, or a bot challenge leaves nothing to thumbnail. If you filter crawlers, allow a user agent containing redditbot, and check your logs for the token Reddit actually sends. redditbot has historically honored robots.txt, so a disallow on the page is a likely reason the fetch never happens. Some communities turn thumbnails off in their settings, and no tag overrides that. Reddit does not publish a minimum image size. Ship 1200×630. A tiny image is a common reason a thumbnail is dropped, but there is no current number to check against.
- After the post exists. There is no Reddit debugger. The preview is chosen when the link is submitted, and editing the tags later does not rewrite that post. Fix the page, then submit again. A query string such as ?v=2 is a different URL, so it is fetched on its own.
Tags covered: og:title · og:description · og:image · og:image:url
More checkers
Twitter Card ValidatorOpen Graph CheckerLinkedIn Link Preview CheckerDiscord Embed PreviewWhatsApp Link Preview CheckerSlack Link Preview CheckeriMessage Link Preview CheckerFacebook Link Preview CheckerOpen Graph Image SizeTelegram Link Preview CheckerNext.js Open GraphRefresh a Link Preview CacheAll platforms
What each platform reads
- X / Twittertwitter:card, twitter:* → og:* fallback1200×630 (min 300×157), < 5 MB
- Facebookog:title, og:description, og:image1200×630, 1.91:1
- LinkedInog:title, og:image (og: only)1200×627, 1.91:1
- Discordog:site_name, og:*, theme-color, twitter:cardLarge image needs summary_large_image
- Slackog:site_name, og:title, og:description, og:image1200×630
- WhatsAppog:title, og:description, og:imageKeep < 300 KB
Guidance based on each platform's public documentation and observed behavior. Platforms change their rules without notice.
FAQ
+Is Peekly free?
Yes. Checking a single URL is free forever — no signup and no limit on one-off checks. Batch watching and monitoring may arrive later as a paid Pro plan; the free single-URL tool stays.
+Why does my link show no image when I share it?
Usually one of four things: there's no og:image tag, the image URL is relative instead of absolute, the image is behind a login, firewall or bot block, or the file is too big or in an unsupported format like SVG. Peekly checks all four and tells you which one it is.
+What size should my og:image be?
1200×630 pixels (a 1.91:1 ratio) as a PNG or JPG under about 300 KB. That size works for large cards on X, Facebook, LinkedIn, Discord, Slack and WhatsApp.
+Do I need twitter: tags if I already have Open Graph tags?
X reads og:title, og:description and og:image as fallbacks, but you still need twitter:card set to summary_large_image if you want the big image card. Without it, X shows a small thumbnail.
+I fixed my tags but the old preview still shows. Why?
Platforms cache link previews, sometimes for days. Facebook and LinkedIn let you force a refresh with their own debugging tools. On X, Slack and Discord the cache usually expires on its own, or you can add a query string such as ?v=2 to the URL.
+Do you store the pages I check?
No. We fetch the page once to read its <head>, show you the result, and don't save the page or the result. We only fetch public http(s) URLs, and private or internal addresses are blocked.
+Are the previews pixel-perfect?
They're close approximations of each platform's current card layout, built from the same tags the platforms read. Platforms change their designs from time to time, so treat them as a very good guide rather than a screenshot.
$9
One time
A written fix for the batch.
Up to 25 URLs. We check og:image, Twitter cards, size, redirects, and cache, then send copy-paste meta tags within 48 hours. The free single-URL check stays free.