MarkupLint

Overview

Instant HTML validation for web developers. Check markup quality offline by AIO.com.ai

MarkupLint is a powerful HTML validation extension for web developers and designers. Instantly analyze any webpage's HTML structure, accessibility, and semantic markup quality without leaving your browser. Press Alt+Shift+V or click the toolbar icon to validate the current page. Results appear in the browser console with color-coded issues, warnings, and suggestions. Features include DOCTYPE validation, heading hierarchy checks, accessibility audits, duplicate ID detection, and semantic HTML5 verification. Works 100% offline with no external requests. Perfect for debugging, learning web standards, and ensuring clean, valid HTML markup. Developed by AIO.com.aiRetry

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Details

Version
1.0.0
Updated
October 29, 2025
Flag concern
Size
26.52KiB
Languages
8 languages
Developer
Email
molawawasaxa@gmail.com
Non-trader
This developer has not identified itself as a trader. For consumers in the European Union, please note that consumer rights do not apply to contracts between you and this developer.

Privacy

The developer has disclosed that it will not collect or use your data.

This developer declares that your data is

Not being sold to third parties, outside of the approved use cases
Not being used or transferred for purposes that are unrelated to the item's core functionality
Not being used or transferred to determine creditworthiness or for lending purposes

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