HTML Validity Report Generator

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🔍 Validate web pages against W3C HTML standards and get detailed quality reports.

✨ What It Does

This Actor validates web pages using the official W3C Nu HTML Checker API. It checks your pages for HTML errors, warnings, and informational messages — helping you improve code quality, SEO, and accessibility compliance.

🔧 How It Works

1. Takes a list of URLs as input
2. Sends each URL to the W3C Nu HTML Checker API
3. Collects validation results (errors, warnings, info messages)
4. Outputs structured data in summary and/or detailed format

📖 How to Use

1. Add URLs — Enter one or more web page URLs to validate
2. Choose Output Mode:
   • Summary — One row per URL with error/warning/info counts and validity status
   • Detailed — One row per validation message with line numbers, code extracts, and descriptions
   • Both — Get both summary and detailed rows (default)
3. Configure Filters — Optionally include or exclude warnings and info messages
4. Run — The Actor validates each URL and pushes results to the dataset

📊 Output Example

Summary Row

{
"url":"https://www.example.com",
"is_valid":true,
"total_errors":0,
"total_warnings":2,
"total_info":1,
"total_messages":3,
"checked_at":"2025-01-15T10:30:00.000000"
}

Detailed Row

{
"url":"https://www.example.com",
"message_type":"error",
"message":"Duplicate attribute \"class\".",
"line":42,
"column":18,
"first_line":null,
"first_column":null,
"extract":"<div class=\"main\" class=\"container\">",
"hilite_start":10,
"hilite_length":15,
"checked_at":"2025-01-15T10:30:00.000000"
}

📝 Notes

• Rate Limiting: The W3C validator is a free public service. The Actor adds a 1-second delay between URL validations to be respectful. For large batches, expect ~1 URL per second.
• Memory: 256 MB is sufficient for most runs. Increase for very large pages (100+ validation messages each).
• Timeout: Default is 30 seconds per URL. Increase for slow-loading pages.
• No API Key Required: Uses the public W3C Nu HTML Checker — completely free, no registration needed.
• Validation Types: Checks HTML5 compliance including proper tag nesting, required attributes, deprecated elements, accessibility issues, and more.