SEO Meta Analyser
Parse HTML to audit title, description, canonical, OG, headings and image alt coverage.
Overview
The SEO Meta Analyser parses an HTML document and produces a single-page audit covering title, meta description, canonical URL, Open Graph and Twitter Card coverage, heading structure (H1–H6 outline), and image alt coverage. Each section reports presence, length, and the most common issues.
Useful for SEO practitioners and developers learning how to audit on-page SEO from HTML or how to check title and description length. Reach for it before publishing a page, when auditing competitor pages, or when triaging which pages in a site need work first.
How it works
The analyser walks the parsed DOM, extracting every meta element by name and property, every heading, every image with or without alt text, and the canonical link. It scores each finding against the well-known guidelines: title 50-60 characters, description 150-160, exactly one H1 per page, no skipped heading levels (H2 to H4 without an H3), every meaningful image with alt text.
Open Graph and Twitter Card coverage is reported as a checklist: title, description, image (with dimension warning if available), URL, type. Missing required tags raise an alert with a remediation tip.
Examples
- Title 38 characters: under recommendation, suggesting a longer descriptive title.
- 12 images, 9 with alt text, 3 missing — flagged with the missing source URLs.
- An H1 missing or present twice — both are flagged with the document's heading outline.
- Open Graph present but
og:imagemissing or under 1200x630 dimensions.
FAQ
Does the analyser fetch the page?
No. It parses whatever HTML you paste, which keeps it offline and fast. Pair with a separate fetcher when you need to audit live URLs.
What's a good title length?
50-60 characters for desktop SERP, shorter for mobile. The Meta Tag SERP Preview tool shows exact pixel truncation; this analyser uses character counts for a quick check.
Are decorative images flagged?
Images with alt="" are treated as decorative and pass the check — that's the accessibility-recommended way to mark them. Missing-alt is flagged separately from empty-alt.
How important is heading hierarchy?
Important for accessibility and moderately important for SEO. Skipped levels confuse screen readers and signal poor structure to search engines. Aim for exactly one H1 followed by logical H2/H3 nesting.