HeadingAlign Pro — Free SEO Heading Hierarchy Checker
HeadingAlign Pro checks and fixes your page's H1–H6 structure. Paste your HTML and it finds missing H1s, skipped levels and out-of-order headings, then shows you the fixed hierarchy — better on-page SEO in minutes.
Why use HeadingAlign Pro?
Search engines read your headings to understand what a page is about. A skipped level or a missing H1 confuses crawlers and hurts rankings — HeadingAlign Pro finds those issues and fixes the structure without touching your words. It checks seven rules and gives you a score out of 100, so you can see exactly how clean a page is before you publish it.
What it can do
Seven checks, one score out of 100
The audit checks exactly one H1, no skipped heading levels, no duplicate H1 text, H1 as the first heading, sensible heading lengths, no unnecessary H5/H6 depth, and no empty headings. Each rule has a weight — the H1 rules count most — and your score is 100 minus the weight of every issue found.
Auto-repair with explanations
One click repairs the hierarchy: the first heading becomes the H1, extra H1s are demoted to H2, levels deeper than H4 are capped at H4, skipped levels are renumbered, and empty headings are removed. Every change is explained in a note, like 'Renumbered H5 on line 12 to H4'.
Three ways to load content
Paste HTML, paste plain text, or upload a .html or .rtf file (RTF is parsed in your browser). Plain-text mode auto-detects Markdown headings, numbered sections and title-case lines, and a Load Example button shows a deliberately broken sample so you can see the audit work.
See the fixed structure
You get an issues list with the rule number, line number and why each issue matters, plus a tree preview of the corrected hierarchy — so you can check the fix before you take the HTML.
Copy or download the fix
The Clean HTML Output panel gives you the corrected page to copy or download as headingalign-fixed.html (or <your-file>-fixed.html when you uploaded one). If your input was not a full document, it is wrapped in a proper HTML shell for you.
100% private, history on your device
Everything runs in your browser — your content is never uploaded, and there are no accounts or API keys. Your last five analyses are saved on your device only, and you can reload or clear them any time.
How to use it
- Paste your HTML or article, or upload a .html or .rtf file. Try Load Example to see a broken page first.
- Click Analyze Structure — or press Ctrl/Cmd+Enter.
- Read your score out of 100 and the issues list, with the rule and line number for every problem.
- Review the fixed structure tree and the repair notes.
- Copy the fixed HTML or download it, then publish the corrected page.
Who is it for?
Built for SEOs, content editors, developers and bloggers who want clean on-page structure before publishing — anyone who writes or reviews pages and needs headings that search engines can actually follow.
Good to know
The tool only fixes heading hierarchy — your words, attributes and non-heading content never change. Plain-text heading detection is heuristic, so double-check unusual formatting. The tool's own page scores a perfect 100/100 on its own seven checks.
Frequently asked questions
What exactly does it check?
Seven rules: exactly one H1, no skipped heading levels, no duplicate H1 text, H1 as the first heading, useful heading lengths, no unnecessary H5/H6 depth, and no empty headings. Each rule has a weight, and your score is 100 minus the weight of every issue found.
How is the score calculated?
Start at 100 and subtract the weight of each issue: missing or multiple H1s cost the most (24), H1 not first costs 14, skipped levels 12, duplicate H1 text 10, empty headings 8, deep H5/H6 5 and heading lengths 4. Zero issues means a Perfect score; 70 or above is Needs Improvement; below 70 is Fix Required.
Does it change my content?
No — it only fixes the heading hierarchy. Your text stays exactly the same, and the rebuild keeps your heading attributes and inner HTML intact. Non-heading content is preserved as-is.
Can I check plain text, not just HTML?
Yes. Paste an article as plain text and the tool detects Markdown headings (# to ######), numbered sections (1., 1.1) and title-case lines automatically, then audits and fixes them the same way.
What do I get after the fix?
A tree preview of the corrected hierarchy, a note for every change made, and clean HTML you can copy or download — as headingalign-fixed.html, or named after the file you uploaded.
Is my content uploaded anywhere?
No. The audit and repair run entirely in your browser — nothing is sent to a server, and your last five analyses are stored only on your own device.