Meta tag checker: test every SEO meta tag on any page
Meta tags control how search engines, social platforms, and AI crawlers describe your page. A missing title, a too-long meta description, or a JavaScript-only canonical can quietly halve your click-through rate. Most meta tag checkers only test the rendered DOM in your browser - they don't tell you what bots actually receive on the wire.
This free meta tag checker fetches your page exactly as a search engine would: a raw HTTP request with no JavaScript execution. You see the title, meta description, canonical URL, robots directives, Open Graph tags, and Twitter Cards that actually live in your initial HTML response - the version that matters most for SEO and the only one available to crawlers that don't run JavaScript.
Each tag is validated against current best practices and length limits. Missing tags, duplicate canonicals, JavaScript-injected meta tags, and invalid Open Graph configurations are flagged with clear explanations of the impact.
Use it before every release to catch tags that disappear in production, or when your page has stopped showing previews on social platforms and you need to know whether the OG tags survived the build. The output is the raw answer - nothing inferred, nothing guessed at - so you know exactly what Google, Bing, GPTBot, ClaudeBot, Facebook, and LinkedIn each see when they fetch your URL.
How to use this tool
- 1
Enter the URL of the page you want to test
- 2
Click 'Check meta tags' to fetch the page as a search engine would
- 3
Review your title and meta description with character-count validation
- 4
Check canonical URL, robots directives, and language attributes
- 5
Verify Open Graph and Twitter Card tags are correct for social sharing
- 6
Fix any flagged issues, redeploy, and re-test to confirm
How it works
This tool sends a server-side HTTP request to your URL using a search engine bot's user-agent. The response contains the exact HTML that crawlers receive - before any JavaScript executes. Most browser-based meta tag checkers test the rendered DOM, which can show meta tags that bots will never see if they're inserted by client-side libraries like React Helmet or Vue Meta.
We extract every standard meta tag from the HTML head: title, meta description, canonical link, robots directive, viewport, charset, lang attribute on the html element, and structured data (JSON-LD). We also pull every Open Graph tag (og:title, og:description, og:image, og:url, og:type, og:site_name) and Twitter Card tag (twitter:card, twitter:title, twitter:description, twitter:image).
Each tag is validated against current SEO and platform requirements. Title length is checked against Google's ~60-character display limit. Meta description is checked against the 155-160 character snippet length. Canonical URLs are validated for self-reference and protocol consistency. Open Graph image URLs are validated for accessibility and recommended dimensions.
Issues are categorised by severity. Critical issues prevent indexing or social previews entirely (missing title, broken canonical, no og:image). Warnings indicate suboptimal configuration (description too long, no Twitter card type, missing alt). Info items are best-practice nudges (consider adding hreflang, structured data, or specific OG tags).
Why this matters for your site
Meta tags are pieces of HTML in the document head that provide structured information about the page to search engines, social platforms, and other automated consumers. Some meta tags directly influence how your page appears in search results (title, description), some control crawler behaviour (robots, canonical), some determine social sharing previews (Open Graph, Twitter Cards), and some are technical hints to the browser (viewport, charset).
The ranking-relevant meta tags in 2026 are surprisingly few. Title and meta description influence click-through rate, which feeds back into rankings. Canonical URL prevents duplicate content penalties. Robots meta tags can block indexing entirely. Open Graph tags don't affect search rankings directly but determine whether your link gets shared and clicked on social media. Outdated tags - like 'meta keywords' - have no effect at all and can be removed.
The critical issue for JavaScript applications is that meta tags often only exist in the rendered DOM, not the raw HTML response. Libraries like React Helmet, Vue Meta, and similar set tags after the page hydrates - which means social platforms, AI crawlers, and Google's pre-render indexing pass don't see them. The most reliable check is to test the raw HTML response, which is exactly what this tool does.
Frequently asked questions
What is the optimal length for a title tag?▾
Google typically displays the first 50-60 characters of a title in search results. Anything longer gets truncated with an ellipsis. Aim for 50-60 characters including spaces. Put the most important keyword first since titles are read left-to-right and front-loaded keywords carry more weight in click-through rate testing.
How long should my meta description be?▾
Google currently displays around 155-160 characters of meta description on desktop, slightly less on mobile (130-150). Longer descriptions are truncated. Aim for 120-155 characters - long enough to be informative, short enough to not get cut off. Include the primary keyword and a clear value proposition or call to action.
Why does my page have meta tags in the browser but not in this checker?▾
Almost certainly because your meta tags are set client-side via JavaScript - typically through React Helmet, Vue Meta, Next.js Head, or similar libraries. This tool fetches the raw HTML response without executing JavaScript, which is what most crawlers and social platforms see. To fix it, render meta tags server-side or use a prerendering service so the HTML response includes them.
Do I still need the meta keywords tag?▾
No. Google ignored the meta keywords tag for ranking signals over a decade ago and has stated it does not use it. Bing, Yahoo, and other major search engines similarly ignore it. You can safely remove meta keywords tags - they consume bytes for no benefit. The only meta tags that still matter for SEO are title, description, canonical, robots, viewport, and structured data.
What is a canonical URL and when do I need one?▾
A canonical URL tells search engines which version of a page is the 'master' when multiple URLs return the same or similar content. You need one for: paginated content, URL parameters that don't change content (utm tracking), www vs non-www, http vs https, and similar near-duplicate situations. Use a self-referencing canonical (canonical pointing to the current URL) on every page as a safety default - it prevents accidental duplicate content issues from URL parameters.
How do robots meta tags differ from robots.txt?▾
robots.txt controls whether crawlers can access a URL at all - if blocked, the page is never fetched. The robots meta tag (in HTML head) controls what crawlers do with the page after fetching it - whether to index it, follow its links, or display a snippet. Common values: 'index,follow' (default - allow indexing and link following), 'noindex' (don't show in search results), 'nofollow' (don't pass authority through links). Robots meta is more granular but only works after the page is fetched.
Are Open Graph tags the same as Twitter Cards?▾
They are similar but separate standards. Open Graph (og:title, og:description, og:image) is Facebook's protocol, also used by LinkedIn, WhatsApp, Discord, Slack, and most other platforms. Twitter Cards (twitter:card, twitter:title, twitter:image) are Twitter/X's own format. Twitter falls back to Open Graph if Twitter-specific tags are missing, so you only strictly need OG tags - but adding both gives finer control over each platform's preview.
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