Step-by-step guide: How to Check the Meta Tags of Any Web Page
How to use the Meta Tag Analyzer
- Open the page you want to check in your browser and view its source code (Ctrl+U on Windows and Linux, ⌥⌘U on a Mac, or right-click and choose View Page Source).
- Select all of the source, copy it, and paste it into the Page HTML box. Alternatively, open an .html file saved on your device.
- Optionally enter the page’s address. The analyzer uses it to turn relative links into full URLs and to tell you whether the canonical tag points to the same page.
- Select Analyze HTML. Each check is marked as passed, a warning or an issue, with a short explanation.
- Fix the issues in your template or CMS, then paste the updated source and analyze again. Use Download report to keep a copy for your records or a client.
Example: a blog post with three common problems
Suppose you paste the source of a blog post and the report shows these results:
| Check | Result | What it means |
|---|---|---|
| Title | Warning — 74 characters | Likely to be shortened in search results. Move the most important words to the front. |
| H1 heading | Warning — 2 found | The theme outputs the site name as an H1 as well as the post title. One clear H1 is easier for readers and assistive technology. |
| og:image | Warning — missing | When the post is shared on social networks, the platform will guess an image or show none. |
| Canonical | Passed | Absolute URL that matches the page address you entered. |
Each of these is a template-level fix, so correcting it once usually improves every post on the site.
What the analyzer checks and why it matters
The <head> of a web page carries instructions that visitors never see but that search engines, social networks and browsers rely on. A missing description or a stray noindex can quietly undo good content, and these problems are easy to miss because the page looks fine in a browser.
The analyzer reads the HTML you supply and reports on:
- Title and meta description — presence, duplicates and length against common display limits.
- Robots meta tags — directives such as
noindexandnofollow, including bot-specific tags likegooglebot. - Canonical link — whether there is exactly one, whether it is absolute and whether it matches the address you entered.
- Open Graph and Twitter Card — the tags that control how links look when shared.
- Language, viewport and character set — basics that affect mobile display and correct rendering of text.
- Headings — the number of H1 elements and the full heading outline.
- Images — images with no
altattribute at all. - hreflang — alternate-language links and whether an
x-defaultis present. - Structured data — each JSON-LD block, whether it parses as valid JSON and which
@typeit declares.
Why you paste HTML instead of entering a URL
Browsers block a web page from reading the content of other websites unless those sites explicitly allow it, a security rule called the same-origin policy. A purely browser-based tool therefore cannot fetch an arbitrary URL. Rather than route your request through a server and pretend otherwise, this tool works on the HTML you provide.
This has two practical advantages. It works on pages that are not public yet — a staging site, a page behind a login, or a draft exported from your CMS — and nothing about the page you are auditing is sent to a third party.
One caveat: “View Page Source” shows the HTML as the server sent it. If a site adds or changes tags with JavaScript after loading, those changes will not appear there. For JavaScript-heavy sites, copy the rendered HTML from your browser’s developer tools instead (right-click the <html> element in the Elements panel and choose Copy outer HTML).
Who finds it useful
Site owners use it to check a new template before it goes live. SEO practitioners use it for quick spot-checks during audits, especially on staging environments that crawlers cannot reach. Developers use it to confirm that a framework’s metadata component outputs what they expect, and social media teams use it to find out why a shared link shows the wrong image or title.
Limitations to keep in mind
- Length guidance for titles and descriptions is a guideline based on typical display widths. Search engines may show a different title or description from the one in your HTML.
- The tool checks structured data for valid JSON and lists its types; it does not validate it against Google’s rich result requirements. Use Google’s Rich Results Test for that.
- Tags added by JavaScript after page load only appear if you paste the rendered HTML rather than the original source.
- HTTP headers, such as
X-Robots-Tagor a canonical sent as aLinkheader, are not part of the HTML and cannot be checked here.
How your data is handled
The HTML you paste or open is parsed by your browser’s built-in DOMParser, which reads markup without running any scripts it contains. The analysis happens entirely on your device. Neither the HTML nor the page address is sent to our servers or anyone else.
Frequently asked questions
Does the analyzer run the scripts inside the HTML I paste?
No. It uses the browser’s DOMParser, which builds a document from the markup without executing scripts, loading images or making network requests. That is also why it is safe to paste HTML from any page.
Is the meta keywords tag worth adding?
Google has stated publicly that it does not use the keywords meta tag for ranking. The analyzer lists it if present, for information, but it is not counted as a problem either way.
Why does my canonical show as a warning?
A canonical is flagged when it is relative (for example /page/ rather than a full URL), when more than one is present, or when it points to a different address from the one you entered. A canonical pointing elsewhere can be intentional — for syndicated or filtered pages — so read it as “check this” rather than “this is wrong”.
What does an empty alt attribute mean?
An image with alt="" is deliberately marked as decorative, which is correct for purely visual images. The analyzer only counts images that have no alt attribute at all, because those give screen readers nothing to work with.
Can I analyze a page that requires a login?
Yes. Because you supply the HTML yourself, you can log in, view the source and paste it. Nothing about your session is involved in the analysis.