SEO Meta Tags Reference
Complete reference for every <meta> tag that matters for SEO, social sharing, and discoverability.
Required — never omit
Important — high impact
Optional / situational
1 · Encoding & Viewport
charset="UTF-8"
viewport
X-UA-Compatible
2 · Page Identity
<title> 50–60 chars
description 120–160 chars
keywords
author
Title + description are what Google shows in SERPs. Write for humans first.
3 · Canonical
<link rel="canonical">
Prevents duplicate-content penalties. Always set — even if the URL is "obvious".
4 · Robots
index, follow
max-snippet:-1
max-image-preview:large
max-video-preview:-1
noindex (private pages)
5 · Open Graph (Facebook, LinkedIn, Discord)
og:type
og:url
og:title
og:description
og:image 1200×630px
og:image:width
og:image:height
og:image:alt
og:site_name
og:locale
og:locale:alternate
article:published_time
article:author
6 · Twitter / X Cards
twitter:card
twitter:title
twitter:description
twitter:image 1200×628px
twitter:site
twitter:creator
twitter:image:alt
7 · Internationalization
<html lang="en">
<link rel="alternate" hreflang="...">
hreflang="x-default"
content-language
8 · Mobile / PWA
theme-color
apple-mobile-web-app-capable
apple-mobile-web-app-title
application-name
9 · Favicons
favicon.ico
apple-touch-icon 180×180
manifest.webmanifest
svg favicon
32×32 + 16×16 png
10 · Performance Hints
preconnect (fonts, CDN)
dns-prefetch
preload (critical CSS/fonts)
11 · Structured Data JSON-LD
WebSite + SearchAction
WebPage
Organization / Person
BreadcrumbList
Article / Product / FAQ
LocalBusiness
Event
JSON-LD is Google's preferred format. Enables rich results (star ratings, breadcrumbs, sitelinks search box).
12 · Verification
google-site-verification
msvalidate.01 (Bing)
yandex-verification
Quick Rules
og:image must be absolute URL (https://), not relativecanonical and og:url must always match- OG image changes take up to 7 days to reflect in Facebook cache — purge via Sharing Debugger
- Twitter ignores
og:* tags if twitter:* are present — always set both
description is not a ranking signal — it affects click-through rate- JSON-LD can go in
<head> or <body> — Google reads both
- One canonical per page — multiple canonicals are ignored