Why a server proxy? Can't this be browser-only?

Browsers can't fetch arbitrary external sites due to CORS. A server proxy is required (every OG tester does this).

What's the recommended OG image size?

1200x630px (1.91:1 ratio) is standard. Works well across Facebook, LinkedIn, and X. Smaller or wrongly proportioned images get cropped or look fuzzy.

How does KakaoTalk preview work?

KakaoTalk prefers og:image, og:title, og:description; falls back to oEmbed or body extraction. This tool simulates KakaoTalk's actual algorithm.

Can I check URLs I don't own?

Yes. Any public URL can be tested — useful for competitive OG analysis.

Are there rate limits?

Per-IP per-minute limits to prevent abuse. Plenty for normal use.

OG Tester

Free Open Graph & Link Preview Tester

Name: Free Open Graph & Link Preview Tester — All Major Platforms
Availability: InStock
Author: Nadoo

One URL. Five platforms. Facebook, X, LinkedIn, Slack, KakaoTalk previews + missing-tag and hreflang diagnostics — all in seconds.

5 platforms from one URL

Enter URL

Paste the page URL and hit Analyze.

5-platform preview

Facebook, X, LinkedIn, Slack, and KakaoTalk cards rendered as they actually appear.

OG tag diagnosis

Missing tags, image size violations, alt text, hreflang — all flagged with SEO recommendations.

Preview cards across platforms

See how one link looks
on every major social platform

Check Open Graph previews for Facebook, X, LinkedIn, Slack, KakaoTalk, and more before you share a page.

Multilingual hreflang check

Auto-validate hreflang
for multilingual sites

Built on Nadoo's own 15-language SaaS expertise — checks hreflang, canonical, and JSON-LD schemas all in one pass.

Frequently asked questions

Only the URL you enter. Our server fetches the public HTML at that URL and parses meta tags. URLs are public information — low sensitivity.

Empty or broken OG can drop
your social CTR by up to 30%

With Nadoo, multilingual OG, Twitter Cards, and JSON-LD are auto-generated. Build SEO-complete multilingual sites in 5 minutes with the AI website builder.

Build a multilingual site free See AI website builder

Feature	This free tool	Nadoo AI website builder
OG card preview	✓	✓ Auto-validation
Auto-generate OG tags	—	✓ Per-page automatic
Multilingual hreflang	Detect only	✓ Auto for 15 languages
Auto JSON-LD insertion	Detect only	✓ Per page type
Auto 1200x630 images	—	✓ AI-generated