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Meta Tag Analyzer

Live-edit every meta tag with pixel-accurate truncation, inline SERP and social previews, AI search visibility checks and a copy-ready fix snippet. No signup.

Last updated: September 2026
💡 AI rewrite uses your daily credits → Settings
10 credits per day

How this meta tag analyzer works

Paste a URL, click Analyze. The tool fetches the page through Lumina's proxy, parses every tag in the head, and scores 17 core checks across SEO, social cards, indexing, schema and accessibility. Duplicate tags, conflicting directives and hreflang errors add to the count when they turn up, and the AI search section reports nine crawlers on top. Title and description get pixel-accurate truncation verdicts for Google desktop AND mobile separately, because wide letters like W and M cut earlier than narrow letters at the same character count.

The new live-edit mode is the part most other tools don't have. After analysis, the title, meta description, og:title and og:description become editable. Type a fix and the pixel bars plus the inline Google SERP preview update on every keystroke. No round-trip to the server, no waiting. One limit worth knowing: the tool reads the HTML the server sends. Tags that JavaScript adds after load won't show up, which on a React, Vue or Angular site can look like missing tags.

What the verdict numbers mean

Old version showed a 0-100 score. New version shows three honest counts: Critical (something is genuinely broken — missing title, noindex on a page you want indexed, HTTP 4xx/5xx, etc), Warnings (works but suboptimal — truncation, missing og:image, hreflang without x-default), Passing (the check ran and there is nothing to fix). A composite score hides which checks failed. Three counts let you see the shape of the problem at a glance — "2 critical, 5 warnings" means the page has 2 things that block performance and 5 things to polish.

AI search visibility: what it actually checks

The AI Search Visibility section fetches the site's robots.txt and reports the access state of nine crawlers: GPTBot, OAI-SearchBot and ChatGPT-User (OpenAI), ClaudeBot and Claude-SearchBot (Anthropic), PerplexityBot and Perplexity-User, plus Google-Extended and GoogleOther. It also requests the page with each bot's user agent to see what the server actually returns. Training and retrieval bots are separate rules: blocking GPTBot doesn't block OAI-SearchBot, which ChatGPT Search uses. And AI Overviews run on regular Googlebot, so blocking Google-Extended doesn't take a page out of them. The tool also probes for an llms.txt file. Results are informational only. Google's own documentation states that Search ignores llms.txt, so the file neither helps nor hurts visibility in Google Search, AI Overviews or AI Mode (Search Central, June 2026). It is shown as a presence flag, never a scored factor.

Twitter Card type-aware validation

Most meta tag checkers list whatever twitter: tags exist on the page. The Twitter Cards spec defines four card types (summary, summary_large_image, app, player), and each has different required fields. A summary_large_image card needs twitter:image; a player card needs twitter:player and twitter:player:width plus twitter:player:height; an app card needs twitter:app:id:iphone and twitter:app:id:googleplay. This tool reads the declared twitter:card value and validates the matching required fields, so a "valid" card is actually valid for its declared type.

Meta Tag Analyzer vs. a full site crawler

One page at a time, that is what this tool does. A site crawler (Screaming Frog, Sitebulb, Semrush Site Audit, Ahrefs Site Audit) processes thousands of URLs and reports meta tags, internal links, response codes, schema and rendering behavior across the whole site. They are complementary. Use this analyzer when debugging one page you just changed. Use a crawler when onboarding a new site or shipping a redesign.

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Get the full analysis in one click

On-page SEO checks, AI crawler analysis, GSC & GA4 dashboards — directly in your browser.

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FAQ

What does the Meta Tag Analyzer check?+
Every meta tag that affects SEO and social sharing: title, meta description, canonical, robots, H1, all Open Graph tags (og:title, og:description, og:image, og:url, og:type, og:site_name, og:locale), Twitter Card tags with type-aware validation, Schema.org JSON-LD types, hreflang with round-trip and x-default checks, viewport, charset, HTML lang attribute, theme-color, favicon, and AI search visibility (GPTBot, ClaudeBot, PerplexityBot, llms.txt).
Can I edit and re-test tags directly in the tool?+
Yes. After analysis, every primary tag (title, meta description, og:title, og:description) becomes a live editable input. Type a change and the pixel-width bars and Google SERP preview update on every keystroke, so you can iterate to a fitting title without leaving the page.
Why pixel widths instead of character count?+
Google truncates titles and snippets to fit the device width, not a character count. Wide letters like W and M push past the limit at lower character counts than narrow letters like i and l. This tool measures rendered pixels in Arial at the sizes Google's result page uses, separately for desktop (20px Arial title, 14px description, 580/920px max) and mobile (18px title, 14px description, 500/780px max), so a 60-character title gets the right verdict for both.
What does Twitter Card type-aware validation mean?+
The Twitter Cards spec defines four card types (summary, summary_large_image, app, player) with different required fields per type. This tool detects the declared twitter:card value and validates the matching required fields, instead of just listing whatever twitter: tags exist.
What is the AI Search Visibility check?+
The tool fetches the site's robots.txt, checks whether nine AI crawlers from OpenAI, Anthropic, Perplexity and Google are allowed or blocked, then requests the page with each bot's user agent. It also probes for an llms.txt file. OpenAI, Anthropic and Perplexity say their bots follow robots.txt. Google AI Overviews are the exception: they use regular Googlebot, so the Google-Extended rule doesn't decide whether a page appears there. llms.txt is shown as informational only since no major AI engine has documented a ranking effect.
Does this tool work with JavaScript-heavy sites?+
Only partly. The tool reads the HTML your server sends and switches to a headless browser only when that first fetch fails outright. Tags that JavaScript inserts after load won't show up here. Google does render JavaScript, but tags already in the server HTML are the safer bet. To compare both versions of a page, use the JavaScript SEO tool (JS vs. No-JS).
How does the AI rewrite work?+
Click "Generate AI Suggestions" after an analysis and the tool sends the current page topic, body context and pixel-width targets to GPT, which returns a new title, meta description, og:title and og:description sized to fit Google's mobile limits, which are the stricter ones, so they fit desktop too. The pixel bars confirm it per suggestion. Suggestions arrive split into auto-applied (paste as-is) and manual (placeholder needs your input), so you never paste broken copy.
Can I analyze pages behind a login?+
No, this tool only analyzes publicly accessible pages. For pages behind authentication, use the Lumina Chrome extension which runs directly in your browser and can analyze any page you have access to.