Why These Tags Matter
Meta tags in the <head> control how your page appears in search results, social shares, and messaging app previews. A missing og:image turns every Facebook share into a bare link. A missing description forces Google to auto-generate one from body text — often pulling in a cookie banner or menu.
Essential Tags
| Tag | Purpose |
|---|---|
<title> | Search result title. 50–60 chars, 500–580px. |
meta description | SERP snippet. 140–160 chars, 820–900px. |
link rel=canonical | Preferred URL for duplicate consolidation. |
meta viewport | Mobile responsiveness signal. |
meta robots | Index/follow directives for crawlers. |
og:title, og:description, og:image, og:url | Facebook, LinkedIn, WhatsApp, Slack previews. |
twitter:card (+ title/description/image) | Twitter/X previews. Falls back to OG if absent. |
The og:image Size Trap
The recommended OpenGraph image is 1200×630px, minimum 600×315px, under 8 MB. If your image is smaller than 200×200px, most platforms won't render a large preview at all — they downgrade to a small thumbnail. Use a 2:1 or 1.91:1 aspect ratio.
Common Mistakes
- Duplicate title/description tags. Some CMSs output one in a template and one in a plugin. Google picks one but you can't control which.
- og:title copied verbatim from title. Not ideal — OG is for humans scrolling social feeds, not search. Write a more emotional or curiosity-driven variant.
- Missing twitter:card. Without it, Twitter/X shows a plain URL. Always include
summary_large_image. - og:image pointing to a localhost URL. Common in staging environments.
- Multiple canonicals. Only one canonical tag is valid. Multiple tags = Google ignores all of them.
Validation Workflow
- Paste your page source's
<head>into the tool above. - Fix every red item (missing essential tags).
- Fix every yellow item (present but suboptimal, e.g. title too long).
- Validate social previews via Facebook Sharing Debugger and Twitter Card Validator.
- Re-check on mobile — some platforms (WhatsApp) cache aggressively and require re-scraping.