Free On-Page SEO Tools

What to fix before you rewrite the page

Title, meta description, H1, and canonical are the tags a template most often gets wrong after a theme or CMS change. Check the URL you want to rank, not the homepage, unless the homepage is the page. A missing canonical, or a canonical that points at a different host, splits the signals for that URL. Duplicate titles across a list are a separate job: paste the URLs into the duplicate title and meta finder instead of opening them one by one.

Heading tools answer a different question from title tools. The H1/H2 extractor and the heading visualizer show the outline in the HTML. They do not score keyword density. The keyword density tool counts terms on one URL, including bigrams and trigrams, so you can see repetition. It is not a ranking score.

Hreflang belongs with on-page only when the page declares alternates. The checker looks for locale codes, return links, and x-default on the URL you paste. It does not crawl the whole cluster. After you change a template, fetch the same URL again. A saved preview in the CMS is not the HTML these tools read.

The content QA checker is for a migration, not a keyword count. You paste the title, meta description, and H1 you expected, and it compares them with the live HTML. Use it when a deploy should have preserved copy and you need to know what changed. Keyword density is the opposite job: it counts what is on the page now, including bigrams and trigrams, and it does not know what you meant to publish.

A sensible pass on one URL is title and meta description, then H1 against that title, then canonical, then headings. Duplicates and hreflang come after, on the list of URLs that share a template. The SEO readiness checker rolls several of those signals into one score. Use it as a queue, then open the single-purpose tool for whatever it flagged.