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Robots.txt Tester
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Heading Structure Checker
Extracts the H1 to H6 outline from HTML and flags skipped levels, multiple H1s and empty headings.
SEO
Nothing uploaded
No sign-up
Free, unlimited
Paste something on the left to see the result.
In short
Heading Structure Checker is a free online tool on inputtesthub.com that extracts the H1 to H6 outline from HTML and flags skipped levels, multiple H1s and empty headings. It needs no account, no download and no payment, and there is no daily usage limit. Everything is processed inside your own browser, so the data you paste is never uploaded to a server.
How to use the Heading Structure Checker
- Paste your code into the input area.
- Choose the indentation and output options you want.
- Read the formatted result, then copy or download it.
About the Heading Structure Checker
The Heading Structure Checker extracts the H1 to H6 outline from HTML and flags skipped levels, multiple H1s and empty headings. It runs as plain JavaScript inside the page, which means there is no upload step, no queue and no size limit imposed by a server — the only limit is your own device.
What people use it for
- Checking a page reads logically for screen readers.
- Fixing a document that jumps from H2 to H4.
- Reviewing content structure before publishing.
Frequently asked questions
Are there any usage caps on the Heading Structure Checker?
There is no cost and no cap. The Heading Structure Checker is not a demo of a paid product, so nothing is held back or watermarked.
Is my data uploaded anywhere?
No. The Heading Structure Checker runs entirely in your browser using JavaScript. Your input never reaches inputtesthub.com or any third party — open your browser's Network tab while you use it and you will see no request go out.
What is the Heading Structure Checker used for?
Typical uses: checking a page reads logically for screen readers. Fixing a document that jumps from H2 to H4. Reviewing content structure before publishing. It is built for exactly those cases rather than being a general-purpose tool with this bolted on.
Is there an app version?
Yes. The page is responsive and the page works in Chrome, Safari, Firefox, Edge and Samsung Internet on both Android and iOS. There is no app to install and nothing to sign into.
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