Online HTML code check

Milten HTML Scanner analyzes page markup, finds validation errors, excessive DOM nodes, duplicate tags, and semantic issues that hurt SEO, speed, and accessibility.

How it works

We check HTML so it is clear what to fix next

Enter a page URL, and Milten loads the final markup, parses the DOM, checks semantics, and builds a practical priority list of fixes.

01 · URL

Capture the final page markup

The scanner opens the URL, waits for the base render, and captures the HTML the user actually gets: server markup, CMS templates, and elements added by scripts.

02 · DOM

Analysis modules

What goes into the HTML report

Each module answers a practical question: where markup became heavy, what blocks indexing, and which fixes should be sent to developers first.

DOM

DOM structure

Shows tree depth, node count, repeated branches, and empty wrappers. The report makes it clear which blocks can be simplified without changing the design.

depthnodesrepeats

FAQ

Frequently asked questions about HTML analysis

Short answers about DOM, validity, HTML size, SEO, and accessibility.

How is HTML Scanner different from a speed check?

Speed Scanner looks at Core Web Vitals, and loading resources. HTML Scanner focuses on markup itself: DOM tree, HTML weight, validity, semantics, accessibility, and technical SEO tags.

Can I check just one page?

Check HTML before errors reach production

Check page structure, validity, semantics, and required meta tags.

Run HTML Scanner

Find structural problems

Milten counts DOM depth, repeated blocks, empty containers, duplicate ids, extra wrapper elements, and fragments that bloat code without value.

03 · REPORT

Build a fix plan

The report shows which issues hurt indexing, accessibility, and maintainability, what can be removed immediately, and which fixes should reach developers first.

Size

HTML weight by category

Breaks the file into content, components, inline CSS/JS, SVG, and comments. This makes it easier to find the source of extra kilobytes and remove it precisely.

contentinlinesvg

Validate

Markup validity

Captures unclosed tags, conflicting ids, invalid attributes, and incorrect nesting. Each issue includes its location and effect.

errorswarningsok

Clean

Duplicates and technical clutter

Finds repeated meta tags, extra canonical/hreflang links, empty div/span elements, and hidden nodes. Recommendations explain what to keep and what to remove.

metaemptyhidden

A11Y

Semantics and accessibility

Checks landmarks, heading order, alt text, form labels, ARIA, and keyboard access so the page is understandable to people and search engines.

landmarkaltaria

SEO

Technical SEO signals

Checks title, description, canonical, robots, hreflang, Open Graph, and structured data. The report notes what affects snippets and indexing.

titlecanonicalschema

Yes. The form accepts the URL of a specific page: homepage, landing page, catalog, product page, or article. For templated sites, it is usually useful to check one page of each type.

Why can large HTML be a problem?

Heavy HTML takes longer to transfer, parse, and maintain. Common causes include inline scripts, large SVGs, repeated cards, extra wrapper layers, CMS comments, and data that should be loaded separately.

Does the scanner show accessibility errors?

Yes, within HTML analysis: form labels, alt text, landmark areas, heading hierarchy, ARIA conflicts, and elements missing semantic roles. A full a11y audit can be a separate step.

What should I do with validator errors?

Start with P1: duplicate ids, incorrect nesting of interactive elements, unclosed tags, conflicting meta/canonical tags, and form issues. After that, clean extra wrappers and improve semantics.