Free
Reference & Standards · Security
Official W3C validator for HTML markup quality.
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Reference & Standards · Security
Official W3C validator for HTML markup quality.
Courses & Tutorials · Documentation & Learning
Beginner-friendly web development tutorials with try-it editors.
Web3 Libraries · Web3 & Blockchain
React hooks for Ethereum — typed, tree-shakeable wallet and contract interactions with multi-chain support.
Desktop Apps · Frontend
Desktop apps using Go backends and web frontends.
Terminals & Shells · Development Environment
AI-powered terminal with blocks, workflows and agent mode.
Accessibility · Testing
Free web accessibility evaluation tool from WebAIM.
Vector Databases · AI for Developers
Open-source vector database with hybrid search and modules.
Courses & Tutorials · Documentation & Learning
Channel YouTube Sandhika Galih — tutorial web development berbahasa Indonesia paling populer, dari HTML sampai framework.
Learning & Reference · CSS Tools
Google's guidance for modern web development and performance.
Color Tools
Check color contrast against WCAG AA and AAA ratios.
E2E & Browser · Testing
Next-gen browser and mobile test automation framework for Node.js.
API Mocking · API Tools
Instantly inspect and test incoming webhooks with a temporary URL.
Build & Lint · Frontend
The widely-used static module bundler for JavaScript applications.
Load & Performance · Testing
Advanced website performance testing from global locations.
Editors & IDEs · Development Environment
JetBrains IDE for JavaScript and TypeScript development.
Agent & LLM Frameworks · AI for Developers
Experiment tracking, model monitoring and ML evaluation platform.
Terminals & Shells · Development Environment
GPU-accelerated terminal emulator multiplexer configurable in Lua.
Whiteboards & Diagrams · Design & Prototyping
Fast workspace for flowcharts, wireframes and mind maps.
Models & LLM APIs · AI for Developers
OpenAI's open-source speech recognition model.
Color Tools
Show how color pairs look across vision types and conditions.
Terminals & Shells · Development Environment
Modern terminal emulator for Windows with tabs, panes and profiles.
AI Coding Assistants · AI for Developers
Agentic AI IDE by Codeium with flow-based coding.
Package Managers · Development Environment
Microsoft's official Windows package manager built into the OS.
API Mocking · API Tools
Flexible API mocking and service virtualization for HTTP.