SEO Checker

What is an SEO checker and what does this one measure?

An SEO checker is an audit tool that looks at a web page the way a search engine does and lists its technical and on-page gaps. This one checks a single URL: it downloads the HTML, reads robots.txt and the sitemap on the same domain, and then groups more than 30 checks into four tabs.

• Meta: title, meta description, canonical, lang, viewport, character set and hreflang.
• Content: H1 and heading order, word count, image alt text, links and an optional focus keyword.
• Technical: status code, redirects, noindex, robots.txt, HTTPS, response time, compression, HTML size, sitemap and structured data.
• Social: Open Graph and Twitter card tags.

I run this kind of scan on the first day of every new project in my SEO consulting work. The reason is simple: lost rankings rarely have an exotic cause. A forgotten noindex, a wrong canonical or one blocking robots.txt line is often enough. The tool turns the findings into a score out of 100 and sorts the fixes by impact.

What does the SEO checker score tell you?

The score is a weighted average of the checks. The three checks that can keep a page out of the index entirely weigh the most: status code, noindex and a robots.txt block, 10 each. Next, the title carries 8; meta description, canonical, viewport, H1, HTTPS and response time carry 6 each. Smaller signals sit between 2 and 5.

A passed check earns its full weight, a warning half, an error nothing. However, I added one more rule: if the page cannot be indexed, the score stays at 49 or below, no matter how polished everything else is. That way a noindex page never looks Good just because its title is nice.

Keep one thing in mind when you read the score: 100 points do not mean the page will rank first. The tool measures the technical and on-page foundation; content quality, competitors and backlinks sit outside this measurement. Still, if the foundation is cracked, nothing you build on top of it pays off fully. So treat the score as a health check, not a ranking forecast.

Which title and meta description lengths are right?

Google publishes no character limit for titles. The Google Search Central documentation says there is no limit on how long a title element can be, but the title link in results gets truncated to fit the device width. That is why the ranges in the tool, 30 to 60 characters for titles and 70 to 160 for descriptions, are practical limits that lower the risk of truncation, not rules.

• Put the topic first and the brand last; if Google cuts the title, the brand goes and the topic stays.
• Do not repeat the same word in a title; Google cites that as an example of keyword stuffing.
• Write a description for each page that describes only that page.

In practice, the Google preview in the report gives you a rough idea of how the title and description will look. For pixel-based measurement, also try the SERP preview tool; the edit link carries your texts over. I explain how to write strong ones step by step in my guide to meta titles and descriptions.

Why might your page not be indexed?

If the Technical tab shows a red row, start there first. The three most common technical reasons a page does not appear on Google are also the heaviest checks in the tool:

1. Status code: Google does not index a page that returns 404, 410 or 5xx. If there are redirects, the tool shows the final URL and every step of the chain.
2. noindex: The tool reads both the meta robots tag and the X-Robots-Tag header. A noindex left over from a staging site is the error I meet most often on new sites.
3. robots.txt: The tool picks the group that applies to Googlebot and applies the longest matching rule; on a tie, Allow wins.

There is a subtle point here: Google cannot see a noindex on a page you block in robots.txt, because it never crawls that page. So if you want a page out of the index, use noindex, not a robots.txt block. To edit the file, try the robots.txt generator. For the definitive indexing status, use URL Inspection in Search Console; the tool shows you where to look.

How does the SEO checker catch canonical and redirect problems?

A canonical tag tells Google which URL you prefer when the same content lives at several addresses. The tool reads every canonical declaration on the page plus the HTTP Link header, then separates four cases: no canonical, a relative URL, a canonical pointing to another URL, or several conflicting URLs.

Google supports relative URLs but notes that they can cause problems in the long run, so it recommends absolute ones. A canonical that points elsewhere is sometimes intentional; for example, a filtered category page may point to the main category. Still, if you see it on a product or service page, that page is most likely not in the index.

For redirects, the tool follows the chain step by step, up to 5 redirects. A single redirect is fine; however, a chain of two or more strains both crawling and speed. For the full chain, use the redirect checker. If you have just moved your site, my website migration SEO checklist will help as well.

How should you read the speed and security signals?

The tool compares server response time with the TTFB thresholds from web.dev: 0.8 seconds or less is good, over 1.8 seconds is poor. I take the measurement from our server, not your browser, and it includes redirects and the HTML download. As a result, the figure can be slightly higher than the real TTFB, and your visitors' location changes it too.

• Compression: if the HTML does not arrive with gzip or Brotli, the transfer size grows for no reason.
• HTML size: Googlebot crawls the first 2 MB of an HTML file; the tool warns above 1 MB.
• HTTPS and mixed content: if an HTTPS page loads images or scripts over http://, browsers may block them.
• HSTS: it does not change the score, but I recommend it once HTTPS is permanent.

That said, this tool is not enough to see full page speed, meaning the weight of images and scripts. For that, I recommend a Lighthouse performance test.

In what order should you fix the issues?

The priority to-do list shows how many points each fix adds and puts the biggest gain first. In client work I follow a similar order:

1. Remove anything that blocks indexing: status code, noindex and robots.txt.
2. Rewrite the title, meta description and H1 around the page's real topic.
3. Turn the canonical into a self-referencing absolute URL.
4. Add supporting signals such as viewport, lang, alt text and structured data.
5. Improve server speed and compression on the hosting side.

Then run the analysis again after each fix; you see the score move right away. You can also scan a competitor's page with the same tool and compare titles, descriptions and structured data. For an assessment that goes beyond one page and covers site structure and crawl budget, take a look at my technical SEO guide.