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Firefox Developer Tools
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Validators

In This Article
    1. Firefox Extensions for Validation
      1. Quick Reference Sidebar Tabs
      2. Checky
    2. Applications and Services
      1. DevEdge Web Tune-Up Wizard
      2. W3C HTML Validator
      3. W3C CSS Validator
      4. W3C RDF Validator
      5. Link Checker
      6. HTML Tidy
      7. HTML Validator Pro
    3. Accessibility Services
      1. Lynx Viewer
    4. Original Document Information

This document lists different resources for developers to validate web pages.

Sidebar tabs are not available at this time.
Tune-up wizard links back to devedge

If you're writing new code that isn't validating immediately, see the available standards-compliant authoring and development tools.

Firefox Extensions for Validation

Quick Reference Sidebar Tabs

Install DevEdge Toolbox Sidebars for quick access to web development references.

Checky

Checky adds a submenu to your Netscape or Mozilla context menu that allows you to run whatever page you're on through one of (currently) 18 different online validaton and analysis services.

Applications and Services

DevEdge Web Tune-Up Wizard

This interface to W3C services guides beginning-to-intermediate web authors through the process of updating content to support Netscape 7.x, Mozilla and other browsers that support W3C Standards.

W3C HTML Validator

The W3C HTML Validator will validate any Web page according to the W3C HTML standards. It is very useful for detecting the use of proprietary HTML as well as invalid HTML.

W3C CSS Validator

The W3C CSS Validator will validate the CSS within any web page or external CSS files according to the W3C CSS standards.

W3C RDF Validator

The RDF Validator service will validate the RDF/XML contained on a given URI.

Link Checker

This tool will check links on a given web page.

HTML Tidy

HTML Tidy is a tool that can be used to report errors in an HTML page and to format web pages for better reading. (Some authoring software, such as HTML-Kit, builds in HTML Tidy which makes validation quick and easy.)

HTML Validator Pro

This is an automated HTML5 checker using the same validator as the W3C. Provide a starting URL and the tool will find and validate all pages in a website.

Accessibility Services

Lynx Viewer

Checks a web page using Lynx visualization and allows validation of accessibility features

Original Document Information

  • Last Updated Date: August 16th, 2002
  • Copyright © 2001-2003 Netscape.

Document Tags and Contributors

Tags: 
  • html5 validator
  • Tools
  • validator
  • Website validator
 Contributors to this page: rralian, ValidatorPro, mcbridematt, Federico, Fredchat, Ptak82, Mathieu Deaudelin, Andreas Wuest, Nickolay
 Last updated by: rralian, May 17, 2015, 12:36:53 PM
  1. Core Tools
    1. Page Inspector
    2. Web Console
    3. JavaScript Debugger
    4. Network Monitor
    5. Performance
    6. Responsive Design Mode
    7. Tips
  2. More Tools
    1. Memory
    2. Storage Inspector
    3. DOM Property Viewer
    4. Developer Toolbar
    5. Eyedropper
    6. Screenshot
    7. Scratchpad
    8. Style Editor
    9. Shader Editor
    10. Web Audio Editor
  3. Connecting the devtools
    1. about:debugging
    2. Connecting to Firefox for Android
    3. Connecting to iframes
    4. Connecting to other browsers
  4. Debugging the browser
    1. Browser Console
    2. Browser Toolbox
  5. Extending the devtools
    1. Adding a panel to the toolbox
    2. Example devtools add-ons
    3. Remote Debugging Protocol
    4. Stream Transport
    5. Source Editor
    6. The Debugger Interface
    7. Web Console custom output
  6. Settings
  7. Release notes