SEO Analyzer

SEO Analyzer takes one URL and returns a complete on-page audit: a score out of 100, a grade, the top three things to fix, and the evidence behind every finding, with no email gate in the way. It checks the things that actually decide whether a page can rank, from whether it can be indexed at all down to whether your images have alt text, and it hands you a prioritised action plan instead of a wall of red.

On-page SEO in 2026

On-page SEO is everything on the page itself that affects how it’s found and understood, as opposed to backlinks and other off-site signals. In 2026 it carries an extra job. The same qualities that make a page rank in Google (clean structure, extractable text, honest metadata, machine-readable identity) are also what make it usable by AI answer engines. The GEO shift means an audit can’t stop at blue links; a page that’s invisible to crawlers that don’t run JavaScript is invisible to ChatGPT and Perplexity too. So this analyzer folds an AI-readiness section into a classic on-page audit, because in practice they’re the same discipline pointed at two audiences.

What each section checks

The report is organised the way you’d actually fix a page, most fundamental first:

• Indexability & canonical. The gatekeeper. A page returning 200 after redirects, with no stray noindex, a sensible canonical, and no robots.txt block for Googlebot. Fail here and nothing else matters: the page can’t rank at all.
• Title & meta description. Present, sensible length, and (if you gave a keyword) relevant. These are your listing in the results and your click-through rate lives here.
• Headings & structure. Exactly one H1, no skipped levels, a logical outline. This is how both readers and machines parse what the page is about.
• Content quality. Depth (word count), readability (a Flesch reading-ease estimate for Latin-script pages), paragraph length, and (with a keyword) where and how often the term appears, flagging both thin content and keyword stuffing.
• Images. Alt-text coverage, no broken markup, lazy-loading hints, and descriptive filenames instead of IMG_1234.jpg.
• Links. Enough internal links, descriptive anchors instead of “click here,” safe target=_blank usage, and no placeholder href="#" dead ends.
• Structured data. Presence of valid JSON-LD, a rich-result type, and an Organization or WebSite entity: a fast check that hands off to Schema Studio for depth.
• Technical basics. HTTPS with no insecure asset references, a viewport meta, a lang attribute, charset, favicon, reasonable HTML size, and a short redirect chain.
• AI readiness. A teaser of the full AI Visibility report: do you allow at least one AI assistant bot, is your content present without JavaScript, and do you have an llms.txt.

Every finding is a row (pass, warning, or fail) with the specific evidence (the actual character count, the actual missing alt tags) and a fix that tells you what to change and where.

How the score is weighted

Transparency is the point, so here’s the arithmetic. The overall score is a weighted sum of the nine sections. Indexability, Title & Description, and Content each carry the most weight (they move rankings the most); Headings, Images, Links, Structured Data, and Technical are mid-weight; AI Readiness is a light teaser here because AI Visibility owns it in depth. Within a section, each check is worth a fixed number of points, and checks that don’t apply (the keyword checks when you didn’t give a keyword, readability on a non-Latin page) redistribute their points to the rest of the section so the total always sums to 100. Grades follow simple bands: A at 90+, B at 75+, C at 60+, D at 45+, and F below. Nothing is hidden or hand-waved: if the tool docks you points, it shows the check, the evidence, and the weight.

From report to action plan

A scored list is only useful if it tells you what to do first, so the analyzer re-sorts every warning and failure by impact times ease (how many points it costs against how hard it is to fix) into “Do now,” “Do next,” and “Nice to have.” Trimming an over-long meta description is a two-minute win with real impact and lands in “Do now”; a full content rewrite lands in “Do next” even if it’s worth more, because ease matters. That prioritised plan is the part people screenshot. Each section also deep-links the specialist Nitro tool with your URL pre-filled: Meta Inspector for the social preview, Schema Studio for structured-data depth, Redirect Tracer for the redirect chain, AI Visibility for the full GEO picture, so the audit is a hub, not a dead end.

For AI agents

This tool exposes a plain-text endpoint designed for language models and agents:

GET https://nitrosites.com/tools/seo-analyzer/scan.php?url=<target>&kw=<keyword>&format=agent

The kw parameter is optional and turns generic checks into keyword-relevance checks. It returns a token-cheap digest of the same analysis shown on this page. Soft rate limits apply; results are cached briefly. No key or login required.

Frequently asked questions

What does an on-page SEO audit check?

Everything on the page itself that affects ranking: whether it can be indexed at all, how the title and description read, heading structure, content depth and readability, image alt text, internal linking, structured data and technical basics like HTTPS and viewport. This tool scores all of it in one pass.

What's a good SEO score?

On this analyzer, 90+ means on-page is basically done and your gains are in content and links; 60–89 means real fixable issues; under 60 usually means fundamentals (indexability, titles, thin content) need attention first. The priority plan sorts it for you.

Do I need to enter a keyword?

It's optional but worth it: with a target keyword the analyzer also checks relevance, whether it appears in your title, H1, opening paragraph and at a sane density, which turns a generic health check into a ranking check.

Why is my beautiful page scoring badly?

The most common culprits are invisible: a stray noindex, a canonical pointing elsewhere, JavaScript-only content, or images without alt text. Beauty and crawlability are different skills: the report shows the exact evidence for each deduction.

Is this a full-site audit?

It's a deep single-page audit. Run it on your money pages: home, services, top posts. For crawl-level issues across hundreds of pages you'd use a site crawler; for making a specific page rank, this is the sharper tool.