Meta Tag Checker — see your page the way Google does
Your title and description at Google's real pixel widths, plus robots and X-Robots-Tag, canonical, hreflang, viewport, Open Graph and icons — with a corrected <head> to copy.
How it works
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Enter any page
We fetch it the way Googlebot does — raw HTML, response headers and robots.txt — so you see what search engines actually receive.
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See your search snippet
Your title and description at the pixel widths Google truncates at, on desktop and mobile, plus every tag that decides whether the page is indexed.
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Copy the fix
Each problem is explained in plain English, and a corrected <head> is ready to paste — every change marked with a comment.
The meta tags that still matter
A page's <head> is a short message to every crawler that visits: what the page is
called, how to describe it, whether to index it, which URL is the real one, which language versions
exist, and how to show it on a phone or in a shared link. Get one tag wrong and the page can vanish from
search, show up with a truncated headline, or split its rankings across duplicates — without anything
looking broken in a browser. This checker reads the head the way Googlebot does, together with the
response headers and robots.txt, and checks every tag that still matters. (The keywords meta
tag isn't one of them: Google has ignored it since 2009.)
Titles and descriptions are measured in pixels
Character limits are a rule of thumb; Google actually truncates by rendered width. On desktop a title gets about 600 pixels of 20px Arial and a description about 920 pixels of 14px Arial; on phones the title wraps to two lines and the description is cut sooner. "WWW" is three times wider than "iii", so two titles with the same length can fare very differently. The preview renders your snippet at those widths and shows where it would be cut.
- Front-load the title. Put what the page is first and the brand last, so a cut costs you the least.
- Keep titles unique. Identical titles across pages are a common reason Google rewrites them.
- Write the description as an invitation. It doesn't change rankings, but it is the sentence that earns or loses the click.
The noindex you can't see
A noindex removes a page from search, and it can live in three places: a
robots meta tag, a googlebot meta tag, or the X-Robots-Tag HTTP
header. The header is the dangerous one — it never appears in the page source, so a staging setting or
a CDN rule can de-index a site while every manual "view source" check looks fine. The checker reads all
three and says where each directive comes from. It also checks robots.txt: a page blocked there can't be
crawled, so Google never sees its tags and may still list the bare URL without a description. To test any URL against your robots.txt for Googlebot and the AI crawlers, use the robots.txt tester.
Canonical mistakes that quietly split your rankings
The canonical URL tells search engines which version of a page to index, so duplicates created by tracking parameters, sorting, filters or print views pass their signals to one URL. Most pages should point at themselves. These are the mistakes the checker catches:
- Two different canonicals, usually a theme and an SEO plugin both adding one — Google then ignores both.
- A canonical in the
<body>, often because a script closed the head early — ignored. - Relative or HTTP canonicals, which break on other hosts and point at the insecure version.
- Canonicals with tracking parameters, which tell Google to index
?ref=navinstead of the clean URL. - A Link header that disagrees with the tag.
Hreflang only counts when it's mutual
Hreflang annotations tell Google which language or regional version of a page to show to whom. They
are easy to get subtly wrong: en-UK instead of en-GB, underscores instead of
hyphens, a page that forgets to list itself, a missing x-default. Above all, every
alternate has to link back — if the German page doesn't point to the English one, Google ignores the
pair. The checker validates the codes and, with one click, fetches up to ten alternates to confirm
the return links.
Mobile, language and encoding
Google indexes the mobile version of every page, so a missing viewport tag — which makes phones render
the desktop layout zoomed out — matters for search, not just for looks. A viewport that blocks zooming
(user-scalable=no or a low maximum-scale) fails WCAG 1.4.4 for people with low
vision. The character encoding must be declared in the first 1024 bytes, and the lang
attribute on <html> tells screen readers which voice to use and search engines which
language they're reading.
Shared links and icons
Open Graph and Twitter Card tags decide how a link looks when it's shared in Slack, LinkedIn, X or iMessage. The checker summarises them; for a pixel-honest preview on six platforms, open the Open Graph preview. It also loads your favicons and touch icons: Google shows a favicon next to your result when it's square and a multiple of 48 pixels.
Copy the fix, then keep it fixed
At the end you get a corrected <head>: your own tags where they're fine, fixed where
they're not, placeholders where something is missing, and a comment on every change. Head tags are also
among the first things a redesign, a plugin update or a CMS migration breaks — silently.
Monity watches your key pages and alerts you when a title,
description, canonical or robots tag changes. For a wider check, run the
SEO & AI visibility audit, test your
structured data with the schema markup validator,
and find dead links with the broken link checker.
FAQ
Common questions
How long should a title tag be?
Google cuts titles by width, not by characters: about 600 pixels on desktop at 20px Arial, which is roughly 50–60 characters of normal text — fewer if it's full of wide letters like W and M. On phones the title wraps to two lines instead. The checker measures your title in pixels and shows exactly where it would be cut, so put the words that matter first.
How long should a meta description be?
Desktop results show about 920 pixels of description (around 150–160 characters), phones about 680 pixels (around 120). Longer descriptions aren't penalised, they're just trimmed. Aim for 120–155 characters that say what the page offers and why to click — the description doesn't affect rankings directly, but it does affect whether people click.
Why does Google show a different title or description than mine?
Google rewrites titles that are too long, stuffed with keywords or identical across pages, often borrowing the main heading or link text instead. Descriptions are replaced even more often, with a passage that matches the search better. You can't force Google's hand, but a concise, accurate title that matches the page's main heading and a specific, unique description get used most.
Where can a noindex hide?
In three places, and the checker reads them all: a robots or googlebot meta tag in the HTML, and the X-Robots-Tag HTTP header — which never shows up in the page source, so it survives every manual check. It also reads robots.txt: if robots.txt blocks Googlebot, Google can't even see the noindex, and the URL can still appear in results without a description.
What is a canonical tag, and what goes wrong with it?
The canonical tells search engines which URL is the main version of a page, so duplicates (tracking parameters, sorting, print views) consolidate their signals. Most pages should point at themselves. The usual mistakes: two different canonicals from a theme and a plugin, a canonical in the <body> (ignored), relative or HTTP canonicals, and canonicals that carry a tracking parameter. The checker flags each one.
How does the hreflang check work?
It validates every hreflang code (en-GB, not en-UK or en_GB), checks that the page lists itself and has an x-default, and — with one click — fetches up to ten alternates to confirm each links back. Hreflang only counts when it's mutual; a missing return link makes Google ignore the pair.
Can I get an alert when my meta tags change?
Yes. A redesign, a plugin update or a staging setting that reaches production can rewrite titles, drop canonicals or add a noindex overnight. Monity watches your key pages and alerts you in Slack, Teams or email when the title, description, canonical or robots tags change. The free plan includes 3 monitors.
One deploy can noindex your site.
Monity catches it the same day.
Monity watches your key pages and alerts you in Slack, Teams or email when a title, description, canonical or robots tag changes — before rankings move.
- Free 7-day trial
- No credit card
- 3 monitors free, forever