Developer Tools
Developer Tools
Section titled “Developer Tools”Professional web development requires the right tools. This page curates essential tools for HTML development, testing, and optimization.
Markup Validation and Quality
Section titled “Markup Validation and Quality”W3C Markup Validator
Section titled “W3C Markup Validator” W3C Markup Validator Official W3C validator for checking HTML validity and conformance to standards.
The W3C Markup Validator checks your HTML against official specifications and reports:
- Syntax errors
- Deprecated elements
- Missing required attributes
- Accessibility issues
- Best practices
How to use:
- Visit validator.w3.org
- Enter your URL or paste HTML code
- Review issues and fix them
- Validate again until your HTML is valid
HTML Linters
Section titled “HTML Linters” ESLint + HTML Plugin JavaScript linter with HTML support for finding code quality issues automatically.
HTMLHint Fast and extensible HTML linter for command-line and editor integration.
html-validate Command-line tool and library for validating HTML.
Accessibility Testing Tools
Section titled “Accessibility Testing Tools”Automated Accessibility Scanners
Section titled “Automated Accessibility Scanners” WAVE (WebAIM Accessibility Evaluation Tool) Browser extension that provides visual feedback about accessibility issues on any web page.
Axe DevTools Comprehensive browser extension for finding and fixing accessibility issues.
Lighthouse Built into Chrome DevTools. Audits performance, accessibility, SEO, and more.
ARIA DevTools Browser extension for inspecting ARIA attributes and roles.
Contrast Checkers
Section titled “Contrast Checkers” WebAIM Contrast Checker Tool for checking color contrast ratios against WCAG standards.
Accessible Colors Interactive tool for finding accessible color combinations.
Polypane Browser designed for responsive design and accessibility testing with built-in checkers.
Screen Reader Testing
Section titled “Screen Reader Testing” NVDA (Free) Free, open-source screen reader for Windows. Most popular free option.
JAWS Industry-standard screen reader for Windows. Commercial license.
VoiceOver (macOS/iOS) Built into Apple devices. Essential for testing on macOS and iOS.
TalkBack (Android) Built into Android devices for testing mobile accessibility.
Browser Developer Tools
Section titled “Browser Developer Tools”Chrome DevTools
Section titled “Chrome DevTools” Chrome DevTools Built into Chrome and Edge. Essential for inspecting, debugging, and testing HTML.
Key features for HTML development:
- Elements panel — Inspect and edit HTML
- Console — Debug JavaScript
- Performance — Analyze Core Web Vitals
- Lighthouse — Audit accessibility, performance, SEO
- Coverage — Find unused CSS and JavaScript
Firefox Developer Tools
Section titled “Firefox Developer Tools” Firefox Developer Tools Built into Firefox. Excellent for HTML inspection and accessibility testing.
Key features:
- Inspector — Inspect and edit HTML
- Accessibility Inspector — View accessibility tree
- Network — Monitor HTTP requests
- Performance — Profile page performance
Safari Web Inspector
Section titled “Safari Web Inspector” Safari Web Inspector Built into Safari. Essential for testing on macOS and iOS.
Code Editors and IDEs
Section titled “Code Editors and IDEs”VS Code (Recommended)
Section titled “VS Code (Recommended)” Visual Studio Code Lightweight, powerful code editor with excellent HTML support. Free and open-source.
Popular HTML-related VS Code extensions:
- HTML Boilerplate — Quick HTML templates
- Live Server — Local development server
- HTMLHint — HTML linting
- Prettier — Code formatting
- Thunder Client — Test APIs
Other Professional Editors
Section titled “Other Professional Editors” WebStorm JetBrains IDE with powerful HTML, CSS, and JavaScript support.
Sublime Text Lightweight, highly customizable code editor.
Vim Powerful, keyboard-driven text editor for command-line development.
Emacs Extensible, customizable text editor popular in developer communities.
Performance Analysis Tools
Section titled “Performance Analysis Tools”Google Lighthouse
Section titled “Google Lighthouse” Lighthouse Automated tool in Chrome DevTools for auditing performance, accessibility, SEO, and best practices.
Metrics it measures:
- Performance
- Accessibility
- Best Practices
- SEO
- Progressive Web App (PWA) features
Core Web Vitals Tools
Section titled “Core Web Vitals Tools” Google PageSpeed Insights Analyzes page performance and shows recommendations for improvement.
WebPageTest Detailed performance analysis tool with waterfall charts and video replay.
GTmetrix Performance analysis combining Lighthouse and WebPageTest data.
Core Web Vitals Report Google Search Console report showing real-world user experience metrics.
SEO and Meta Analysis
Section titled “SEO and Meta Analysis”SEO Auditing Tools
Section titled “SEO Auditing Tools” Screaming Frog SEO Spider Desktop crawler for analyzing on-page SEO elements, broken links, and metadata.
Semrush Comprehensive SEO toolset for audits, keyword research, and competitive analysis.
Ahrefs Enterprise SEO platform with site audits and backlink analysis.
Moz SEO tools including site crawlers and rank tracking.
Meta Data Validators
Section titled “Meta Data Validators” Open Graph Debugger (Meta) Facebook's tool for validating Open Graph tags and previewing social sharing.
Twitter Card Validator Tool for validating and previewing Twitter Cards.
Google Structured Data Testing Tool Validate JSON-LD and other structured data formats.
Responsive Design Testing
Section titled “Responsive Design Testing” Chrome DevTools Device Mode Built-in responsive design testing in Chrome DevTools.
Responsively App Free desktop app for testing responsive designs across multiple devices.
Polypane Browser specifically built for responsive design with multiple viewport views.
BrowserStack Cloud-based testing platform for testing on real devices and browsers.
Browserling Interactive cross-browser testing in the cloud.
Browser Compatibility
Section titled “Browser Compatibility”Checking Support
Section titled “Checking Support” Can I Use Comprehensive browser support tables for web features. Essential reference.
MDN Browser Compatibility Charts Browser support information included in MDN documentation.
HTML5 Test Test your browser's support for HTML5 features.
CSS Support Check CSS feature browser support.
Link and Image Analysis
Section titled “Link and Image Analysis”Link Checkers
Section titled “Link Checkers” W3C Link Checker Official tool for checking links on a page.
Broken Link Checker Online tool for finding broken links.
Dr. Link Check Desktop application for checking links in local and remote files.
Image Optimization
Section titled “Image Optimization” ImageOptim App for optimizing image sizes without quality loss.
TinyPNG / TinyJPG Online image compression service with excellent quality preservation.
Squoosh Google's web app for image compression and format conversion.
ImageSizing Online tool for resizing and optimizing images for web.
Semantic HTML Tools
Section titled “Semantic HTML Tools”HTML Outliner
Section titled “HTML Outliner” HTML5 Outliner Visualizes the document outline based on heading hierarchy and sectioning elements.
Use this to verify:
- Proper heading hierarchy
- Correct nesting of sections
- Clear document structure
- SEO-friendly organization
Testing Frameworks
Section titled “Testing Frameworks”HTML Testing
Section titled “HTML Testing” Playwright Modern testing framework for automated browser testing including HTML validation.
Cypress End-to-end testing framework with excellent developer experience.
Jest Testing framework with DOM testing capabilities.
Vitest Unit test framework for JavaScript and HTML components.
Build Tools
Section titled “Build Tools”HTML Processing
Section titled “HTML Processing” HTML-Webpack-Plugin Webpack plugin for generating HTML files.
posthtml Tool for transforming HTML with JavaScript plugins.
Pug (formerly Jade) Clean, whitespace-sensitive template language for HTML.
EJS Embedded JavaScript templating for HTML.
Code Quality and Formatting
Section titled “Code Quality and Formatting” Prettier Code formatter that enforces consistent style.
Stylelint CSS linter for finding and fixing problems in CSS.
ESLint JavaScript linter for finding and fixing problems in code.
EditorConfig Maintain consistent coding styles across different editors and IDEs.
Documentation and Learning
Section titled “Documentation and Learning”Interactive Learning Platforms
Section titled “Interactive Learning Platforms” MDN Web Docs Comprehensive, community-maintained documentation for all web technologies.
W3Schools Beginner-friendly tutorials and references for web technologies.
DevDocs Offline-capable documentation browser for multiple technologies.
Summary
Section titled “Summary”Essential tools every HTML developer should know:
- W3C Markup Validator — Validate HTML
- Chrome DevTools — Inspect and debug
- WAVE/Axe DevTools — Check accessibility
- Lighthouse — Audit quality
- Can I Use — Check browser support
- VS Code — Code editor
- Firefox DevTools — Alternative browser testing
- Screaming Frog — SEO auditing
Start with the essentials and add more tools as your development needs grow.