Free Online Browser Compatibility Feature Support Checker

Overview

A high-performance, single-file browser utility designed to act as a lightweight, instant-search reference for web feature compatibility. Developers can search for CSS, HTML, or JavaScript features to see a matrix of supported browser versions.

Key Features

• Instant-Search Interface: A reactive search bar that filters the feature database as the user types.
• Categorized Indexing: Features are tagged by type (CSS, HTML, JS) to allow users to narrow down results quickly.
• Visual Support Matrix: A clear, color-coded grid displaying 'Supported' (Green), 'Not Supported' (Red), and 'Partial Support' (Yellow) status for major browsers.
• Version Requirements: Hover-over tooltips that display the specific version number where support was introduced.
• Mobile-First Data Tables: Tables are optimized to collapse into mobile-friendly stacks, ensuring readability on smaller screens.

UI/UX Design

• Aesthetic: Clean, SaaS-style interface. Uses a light-mode palette consisting of crisp whites, soft grays, and primary brand blues for action buttons.
• Header: Contains a simple title and a "Clear Search" reset button.
• Main Content: A prominent search input field with a subtle bottom-shadow, followed by the result cards.
• Results Area: When a user selects a feature, a detailed view expands with a card displaying the "Browser Support" table, documentation links, and syntax examples.
• Animations: Subtle fade-in/out transitions when searching or filtering results. Use CSS transitions for the expansion of result cards.

Developer Constraints & Technical Implementation

• Architecture: Single-file application using Vanilla JS, HTML5, and Tailwind CSS (via CDN).
• Sandboxed Execution: Must work in a restricted iframe environment. DO NOT use localStorage, sessionStorage, or cookies. Data must be held in a static JSON object constant within the script tag.
• Search Logic: Use a performant array filter method on the main data object to ensure sub-millisecond search responses.
• No External Dependencies: Minimize external JS libraries. Use native DOM manipulation for all interactive elements.
• Accessibility: Ensure high contrast for status badges and keyboard navigation for search inputs.
• Responsiveness: Use media queries to switch from multi-column grid layouts on desktop to full-width lists on mobile devices.