Meta tags are invisible to your visitors but visible to every crawler, bot, and social platform that touches your URL. When they're correct, search results and share previews look sharp without any extra effort. When they're broken or missing, the consequences show up as lost clicks, broken previews, and pages that search engines misunderstand.
This guide covers every tag you need to audit — and exactly what "fixing" each one means.
What Gets Audited (and Why Each Tag Matters)
Title Tag
<title>Page-Specific Title | Site Name</title>
This is the single most important on-page SEO element. Google displays it in search results. It's what users click on. Best practices:
- 30–60 characters. Google truncates titles above ~580px display width — roughly 60 characters. Under 30 characters and you're leaving keyword space on the table.
- Unique per page. Every page with the same title signals to Google that the pages are duplicates.
- Front-load the keyword. The topic should appear in the first few words, not at the end.
Meta Description
<meta name="description" content="A concise summary under 160 characters." />
Google doesn't use meta descriptions as a ranking factor — but they directly affect click-through rate. A well-written description explains the page's value proposition in search results.
- 70–160 characters. Under 70 is too thin. Over 160 gets truncated.
- Include a call to action. "Learn how…", "See the full list…", "Download free…"
- Match search intent. The description should confirm what the searcher expects to find.
If you don't write one, Google will generate its own — usually a snippet pulled from the middle of your content, which may be irrelevant or cut awkwardly.
Canonical URL
<link rel="canonical" href="https://yoursite.com/this-page" />
The canonical tag tells search engines which version of a page is the "real" one. Without it, Google may find the same content at multiple URLs (with vs. without trailing slash, http vs. https, www vs. non-www, filtered query params) and split link equity across duplicates.
This is especially important for:
- E-commerce sites with product filtering (
?color=red,?size=xl) - Content syndication (if you republish articles elsewhere)
- Pagination (
/blog?page=2)
Robots Meta Tag
<meta name="robots" content="index, follow" />
Controls whether search engines index the page and follow its links. Key values:
| Value | Effect |
|---|---|
| index | Allow indexing (default) |
| noindex | Exclude from search results |
| follow | Follow links on the page (default) |
| nofollow | Don't pass link equity to outbound links |
| noarchive | Don't show a cached version |
Most pages should have no robots tag (defaults to index, follow). Use noindex for admin pages, thank-you pages, and staging environments you don't want in search results.
Open Graph Tags
Open Graph (OG) tags control how your page appears when shared on Facebook, LinkedIn, iMessage, Slack, and most other platforms.
og:title and og:description
<meta property="og:title" content="Your Page Title" />
<meta property="og:description" content="Description for social cards." />
These can (and should) differ from the <title> and <meta name="description">. The title tag is optimized for search result click-through. The OG title is optimized for social engagement — it can be more conversational or curiosity-driven.
Character limits:
og:title— 70 characters before truncation on most platformsog:description— 200 characters on Twitter, less on others
og:image
<meta property="og:image" content="https://yoursite.com/og.png" />
This is the image that appears in the preview card. It's the highest-impact element for social sharing — a relevant, eye-catching image can dramatically increase click-through rate.
Requirements:
- Absolute URL, HTTPS. Relative paths and HTTP images are ignored.
- 1200×630px (1.91:1 ratio). This works on all major platforms. Smaller images get upscaled and look blurry.
- Publicly accessible. No authentication, no CDN restrictions.
- Under 5MB (Twitter), under 8MB (Facebook).
og:url
<meta property="og:url" content="https://yoursite.com/this-page" />
Specifies the canonical URL for the shared content. If someone shares a URL with query parameters, this ensures the preview points to the clean URL.
og:type
<meta property="og:type" content="article" />
Use "website" for general pages and "article" for blog posts and news content. Using "article" unlocks additional structured data support for author and publish date on some platforms.
og:site_name
<meta property="og:site_name" content="Your Brand Name" />
Displayed below the card title on most platforms. Reinforces brand recognition.
Twitter Card Tags
Twitter reads OG tags as a fallback, but explicit Twitter Card tags give you more control:
<meta name="twitter:card" content="summary_large_image" />
<meta name="twitter:title" content="Your Page Title" />
<meta name="twitter:description" content="Description for Twitter." />
<meta name="twitter:image" content="https://yoursite.com/twitter-image.png" />
<meta name="twitter:site" content="@yourtwitterhandle" />
summary_large_image shows a large image card — significantly higher engagement than summary (small thumbnail). If you're only adding one Twitter tag, make it twitter:card.
Technical Tags
Viewport
<meta name="viewport" content="width=device-width, initial-scale=1" />
Required for mobile responsiveness. Missing this tag causes Google to classify your page as not mobile-friendly, which negatively impacts ranking in mobile search results.
Theme Color
<meta name="theme-color" content="#3a1f1a" />
Sets the browser chrome color on mobile. Primarily aesthetic, but contributes to a polished first impression.
A Complete Audit Template
When auditing a page, work through this list:
Primary SEO:
- [ ] Title: 30–60 characters, unique, keyword-first
- [ ] Meta description: 70–160 characters, action-oriented
- [ ] Canonical: present and pointing to the intended URL
- [ ] Robots: absent (defaults) or intentionally set
Open Graph:
- [ ] og:title: present, under 70 characters
- [ ] og:description: present, 50–200 characters
- [ ] og:image: HTTPS absolute URL, 1200×630px, publicly accessible
- [ ] og:url: present, matches canonical
- [ ] og:type:
articlefor blog posts,websitefor others - [ ] og:site_name: present
Twitter:
- [ ] twitter:card:
summary_large_image - [ ] twitter:title, twitter:description, twitter:image: present
- [ ] twitter:site: brand handle
Technical:
- [ ] viewport: present
- [ ] No HTTP images in any meta tag
Audit Any URL Instantly
Our Meta Tag Analyzer checks every tag on this list in seconds. Paste any public URL — it fetches the page, parses all meta tags, and returns a pass/fail report with character counts, length warnings, and a live social preview showing exactly how the page will appear when shared.
For pages you manage, run this audit after every major content update or site migration. For competitor research, it's the fastest way to understand what tags they're using and where the gaps are.