HTML & Web Developer Resources

The most comprehensive and developer-friendly HTML element reference available. Covers every element, attribute, and usage example.

The official HTML specification maintained by WHATWG. The authoritative source for how HTML is defined and should behave.

The official W3C HTML validator. Paste a URL, upload a file, or paste code directly for a detailed spec-level validation report.

Beginner-friendly HTML tutorials and references covering all core elements with live code examples you can edit in the browser.

A visually clean, free HTML element reference with live examples for every element and attribute. Great for quick lookups.

Check browser support tables for HTML, CSS, and JavaScript features. Essential before using any newer HTML element or attribute in production.

Complete CSS property reference with browser compatibility tables, syntax examples, and detailed explanations for every property.

Visual CSS property reference with illustrated examples showing exactly how each property affects rendered output.

The definitive visual guide to CSS Flexbox. Explains every property with clear diagrams — the most-referenced CSS layout resource online.

Comprehensive visual guide to CSS Grid with illustrated examples of every property. The standard reference for grid layout.

Visual gradient builder that generates clean CSS gradient code. Supports linear, radial, and conic gradients with live preview.

Generate smooth, layered CSS box shadows with a visual editor. Produces much more natural-looking shadows than single-layer defaults.

Fast colour palette generator. Press the spacebar to generate new palettes, lock colours you like, and export in multiple formats including CSS variables.

Curated collection of colour palettes submitted by designers. Browse by trend, season, or style and copy hex codes instantly.

Check whether text and background colour combinations meet WCAG accessibility contrast requirements. Essential for accessible web design.

Generate Tailwind-compatible colour scales from any base colour. Exports as CSS variables, Tailwind config, or hex values.

Enter any public URL to get a visual accessibility report with errors, warnings, and structural information overlaid directly on the page.

The official W3C quick reference for Web Content Accessibility Guidelines 2.1. Filterable by level (A, AA, AAA) and category.

A practical, developer-friendly accessibility checklist based on WCAG. Organised by category with clear pass/fail criteria for each item.

MDN's comprehensive learning resource for web accessibility. Covers semantic HTML, ARIA, keyboard navigation, and assistive technology basics.

Google's tool for measuring Core Web Vitals and page performance on mobile and desktop. Gives actionable recommendations to improve scores.

Detailed page speed analysis with waterfall charts, filmstrip view, and historical tracking. Great for diagnosing specific loading bottlenecks.

Monitor your site's presence in Google Search. Track indexing status, Core Web Vitals, search queries, and click-through rates. Free and essential.

Advanced performance testing from real browsers in real locations worldwide. Provides detailed waterfall analysis and Core Web Vitals breakdown.

Free, structured curriculum covering HTML, CSS, JavaScript, and more with hands-on projects and a recognised certification on completion.

Mozilla's structured learning path for web development. Starts from absolute basics and progresses through HTML, CSS, JavaScript, and accessibility.

Browser-based code editor for HTML, CSS, and JavaScript with instant live preview. Perfect for experimenting with ideas and sharing demos.

One of the most respected front-end development blogs. Deep-dive articles, guides, and almanac entries covering HTML, CSS, and JavaScript techniques.

Google's developer resource for modern web best practices. Covers performance, accessibility, progressive web apps, and Core Web Vitals with practical guides.

Industry-leading publication for web designers and developers. In-depth articles on HTML, CSS, UX, performance, and front-end best practices.