Is SEO KING free to use?

Yes. Paste a URL on the home page and the full report opens without an account — every check is included, with no trial, credit limit or credit card. Signing in with a one-time email code is only needed to keep a history and re-check pages on a schedule.

How is the score calculated?

Each of the 48 checks carries a weight based on how much it influences on-page SEO. A passing check earns its full weight, a warning earns half and a failure earns nothing. The total is divided by the maximum possible weight and shown out of 100.

What exactly gets checked?

Five areas. Basics covers HTTPS, status code, language, encoding, mobile viewport, URL readability, tracking parameters and legacy markup. Content covers the title, meta description, headings, word count, image alt text and the text-to-markup ratio. Sharing covers Open Graph and Twitter/X cards. Technical covers the canonical URL, indexability, structured data types, mixed content, HSTS, favicon and external link safety. Performance covers document size, resource count, response time, compression, caching, redirects, render-blocking and third-party scripts, image sizing, lazy loading and modern image formats.

Does it work on any website?

Any publicly reachable HTML page. SEO KING follows redirects and reports non-HTML responses as un-auditable. Pages behind a login cannot be audited, because the fetch happens without your browser session.

Does it change my website?

No. SEO KING only reads the page you give it. Nothing is written back to your site and nothing has to be installed.

How should I use the report?

Work top-down. Findings are ordered critical first, then warnings, then passing checks, and every finding carries a specific fix. Re-run the audit after each round of changes to watch the score move.

Can I export or share a report?

Yes. Copy the report as Markdown, or download it as Markdown or JSON from the export menu, so it can go straight into a ticket or a task for a developer.

Who can see my audit history?

Only you. Every run is stored against your own account, and the dashboard only ever shows your own history.

Can I audit a YouTube video?

Yes. Paste a watch, shorts or youtu.be link into the YouTube audit and SEO KING reads the live page: title and description length, keyword placement, tag count and coverage, thumbnail resolution, caption tracks, hashtags, chapters, likes against views, age restriction and crawlability — 21 weighted checks with a fix for every finding.

Are the SEO tools free?

Yes. The SERP snippet preview, social card preview, heading outline, hreflang checker, meta tag generator, robots.txt builder and checker, JSON-LD schema generator, keyword density analyser, llms.txt generator and UTM campaign builder need no account, and what you paste into them is measured in your browser and never uploaded. Each tool also offers a live check: give it a URL and the server fetches that page so you see the tags, robots.txt, text or redirect chain that is genuinely being served.

What is a canonical URL?

The canonical URL is the one address a page wants search engines to treat as the real version, so copies and parameter variants do not compete with it. A page that points at a different URL, or at nothing, can split its own ranking signals across several addresses.

What is hreflang used for?

hreflang tells search engines which language and region each copy of a page is for, so the right version is shown to the right reader. The set only works when every page points at itself and the others, uses absolute URLs, and includes a default for readers who do not match a language.

Does structured data improve rankings?

Structured data does not raise rankings by itself, but it makes a result eligible for rich results that earn more clicks — stars, FAQs, breadcrumbs, videos and product snippets. The markup must match what is visible on the page, or it is ignored.

What is a good SEO score?

A score above 80 usually means the page is technically sound and the content signals are in place. The score is a starting point, not a target: a page can score well and still not rank if the content does not answer the query better than the pages already there.

Which SEO tools are on the site?

The site offers twenty-one free browser tools: a SERP snippet preview, a meta tag generator, a robots.txt builder and checker, a JSON-LD schema generator, a keyword density analyser, a UTM campaign builder, a social card preview, a heading outline checker, a hreflang checker, a llms.txt generator, an AI visibility check, a redirect chain tracer, an XML sitemap checker, a link extractor, a URL encoder and decoder, a URL slug generator, an indexability audit, a crawl and internal link audit, a duplicate content audit, a performance and Core Web Vitals audit, and a site-wide index coverage audit. Each one can check a live URL.

Free SEO audit and YouTube SEO checker

SEO KING is a free on-page SEO audit for any URL and a YouTube SEO checker for any video, backed by thirteen browser tools. Submit one page and it is fetched live, then scored against 48 weighted on-page checks — and every finding comes back with a specific fix.

What the free SEO audit checks

One run covers the five areas that decide how a page performs in search. Foundations look at HTTPS, the HTTP status code, language, character encoding, the mobile viewport, URL readability, tracking parameters and legacy markup. Content inspects the SEO title, the meta description, the H1 and heading order, body word count, image alt text, the text-to-markup ratio and placeholder copy. Distribution reads the Open Graph tags, the shared preview image and the X card. Technical covers the canonical URL, indexability, structured data, mixed content, the HSTS header, the favicon and external link safety. Performance measures document weight, resource count, response time, compression, caching headers, redirect chains, render-blocking and third-party scripts, image dimensions, lazy loading and modern image formats.

YouTube SEO audit

Paste a watch, shorts or youtu.be link and the same account reads the live page: title length and keyword placement, description depth, tag count and coverage, thumbnail resolution, caption tracks, chapter timestamps, likes against views, age restriction and crawlability — 21 weighted video checks, each with a recommendation.

Twenty-one free SEO tools

Every tool can check a live URL instead of a draft, so what you see is what the server is actually sending. They run in your browser and need no account.

SERP snippet preview — pixel-accurate title and description truncation for desktop and mobile.
Meta tag generator — audits a page's head, then generates a copy-paste meta tag block.
Robots.txt builder and checker — validates the rules and proves every declared sitemap resolves.
JSON-LD schema generator — reads the structured data a page already declares and builds Article, FAQ, Product and VideoObject markup.
Keyword density analyser — word, sentence and phrase frequency for a draft or a live page.
UTM campaign builder — reports the redirects it followed and whether every utm_ value survived to the final URL.
Social card preview — renders the feed and compact share cards a page's Open Graph tags produce.
Heading outline — the H1-H6 structure a page serves, with missing or skipped levels flagged.
Hreflang checker — every language declaration, its self-reference and its x-default.
llms.txt generator — a validated Markdown map of a site for AI search.
AI visibility check — whether the answer-engine crawlers may read the page, and whether it reads like an answer.
Redirect checker — every hop a URL takes, with the status code and destination of each one.
XML sitemap checker — validates a sitemap and requests a sample of the URLs it lists.
Link extractor — every anchor a page serves, with the unsafe new-tab links and bare anchors flagged.
URL encoder & decoder — escape a URL or fragment for safe use, or read an encoded one back.
URL slug generator — turn a title into a clean, lower-case path segment.
Indexability audit — the status, robots.txt rule, noindex source or canonical that stops a URL from being indexed, plus whether the sitemap lists it.
Crawl & internal link audit — requests a page's internal links and cross-checks them against the sitemap, so broken or orphaned pages surface before a crawler finds them.
Duplicate content audit — compares two URLs for shared titles, headings and body copy, and tells cannibalisation apart from a shared topic.
Performance & Core Web Vitals audit — time to first byte, compression, blocking head tags, third-party origins and the real transfer size of the LCP image.
Site index coverage audit — samples the sitemap and names the pages Google cannot index, with the reason on each one.

Every SEO check, explained

The full audit runs 48 weighted checks across five areas: foundations, content, distribution, technical and performance. The reference page lists every check with its threshold and the fix that turns it green.

Public SEO reports, measured live

Each row on the public reports hub is a real site checked against the same 48 weighted on-page checks, stored at a permanent address so it can be linked, shared and re-checked. Anyone can run the same audit on their own page without an account, and the result is published at /report/<host>.

YouTube SEO audit

Audit a YouTube video — 21 weighted checks

How the score works

Each check carries a weight based on how much it influences on-page SEO. A pass earns its full weight, a warning earns half and a failure earns nothing; the total is shown out of 100 with a letter grade. Findings are ordered critical first, then warnings, then passing checks, so the report reads as a worklist. Mark a finding as fixed, re-run the audit and watch the score trend for that page.

Start here

Start with a guide

Guides from the search community

SEO KING reads pages only. Nothing is written back to your site, no snippet of code has to be installed, and the audits you run stay in your own private history. Read the privacy policy and the terms of use.