HTML Validator
Check HTML tag balance — unclosed tags, mismatched nesting, and misused void elements.
Runs locally in your browser. Your input is not uploaded.
How to Use
- 1
Paste your HTML
Full pages or fragments — script/style contents are skipped.
- 2
Read the issues
Each unclosed or mismatched tag is listed with its line.
- 3
Fix from the top
Early errors often cascade — fix the first ones first.
Frequently Asked Questions
- Tag balance: unclosed elements, closing tags with no opener, improperly interleaved nesting, and closing tags on void elements like <br> — each reported with its line number.
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