What an on-page SEO check covers
On-page SEO is everything a search engine can read in the page itself, before links and reputation come into it. This audit fetches the raw HTML, the way Googlebot first sees it, and checks the signals that most often go wrong:
- Title tag. Present, one of them, 30–60 characters. It is the blue link in search results.
- Meta description. Present and 120–160 characters. Google rewrites it often, but a good one still wins clicks.
- One H1. The page's main heading, stating the topic.
- Canonical URL. One canonical, so duplicate URLs consolidate. The canonical checker goes deeper.
- Indexability. No
noindexin the robots meta tag or the X-Robots-Tag header. This is the single most expensive mistake on the list. - Mobile viewport, HTTPS and lang. The basics of mobile-first indexing and accessibility.
- Social tags. Open Graph and Twitter card tags for link previews.
- Images, words, links and schema. Alt coverage, enough visible text to rank, internal links to go deeper, and JSON-LD structured data.
- Response time. How long the server took to answer.
How the score works
Each check has a weight. Indexability, the title and the H1 weigh most; a missing Twitter card weighs least. A pass earns the full weight, a warning half, a failure nothing. The score is the share earned, out of 100. Use it to track one page over time, not to compare unrelated sites.
What this audit does not see
It reads the HTML your server sends. Content rendered later by JavaScript is invisible here, and often slower for search engines to find as well. It also cannot judge whether the page answers the searcher's question, which is what ranks in the end. Pair it with the heading analyzer to check structure and the broken link checker to catch dead ends.
A quick fix order
- Remove any accidental
noindex. - Write a specific title and meta description.
- Make sure there is exactly one H1.
- Add a self-referencing canonical.
- Fill in Open Graph tags and image alt text.