331 best development tools and websites

Animated component set for showing an AI thinking state in a product.

Chrome extension for testing and previewing a website on more than 80 phone, tablet and desktop screens.

Opinionated shadcn registry of copy-paste UI components for React and Svelte 5.

Copy-paste React components for AI chat agents, thinking states and human-in-the-loop flows.

Overlay browser that floats any website on top of whatever app you are in.

Generate text, images and video from the command line.

Preview any URL or localhost on 123 real phone, tablet, laptop and monitor sizes.

Open source React library for generating unique SVG avatars from names.

Round, flat, designer-friendly pseudo-3D engine for canvas and SVG.

Theme your own design system, then install its Vue or React components as source code that your coding agents can read and extend.

React component library of 65+ production components with a matching Figma file.

Stateful API emulation so integrations can be tested in CI.

accessibility engine designed to work on all modern browsers and with whatever tools, frameworks, libraries, and environments you use today.

Reduce your image size without compromising on quality. Experience the best JPEG and image compression tool online.

Scraping API that returns structured data instead of raw HTML.

Framework-agnostic toolkit for building drag and drop interfaces.

Motion toolkit of animated components for React and Next.js.

Enterprise-class design language and React UI library with a large set of components.

Free open-source desktop app that handles the shipping steps freelancers repeat.

Google's open source tool for auditing web performance, accessibility, SEO and best practices.

Microsoft's free tools for finding and fixing accessibility issues in web, Windows and Android apps.

Open-source browser API for running and controlling cloud browsers at scale.

See the tech stack behind any website, from CMS to analytics.

Mac and iOS app that makes App Store Connect faster for updates, localization and releases.

Accessible one-time password input for React, styled to fit.

Browser automation CLI built for AI agents, with debugging built in.

Form endpoint that collects submissions without writing a backend.

End-to-end testing that writes and maintains the tests with AI.

Animated number component for React with accessible transitions.

Opinionated toast component for React, sensible defaults out of the box.

TypeScript SDK for transactional email across providers, one clean API.

Open-source HTML-in-canvas and WebGL components for framework-agnostic web effects.

Real-time animated line chart component for React.

Open-source framework for connecting AI agents across messaging platforms.

Directory pairing popular paid software with its open-source alternatives.

API for adding, verifying and monitoring customer domains.

Free, open-source collection of unusual animated React components.

Drop an HTML file in and get a live link back.

Terminal UI core written in Zig with TypeScript bindings for building CLIs.

Open-source starter kit and UI library for building AI design apps.

One API across several sandbox providers for running untrusted code.

Editor themes built for long sessions, tuned for clarity over contrast.

Swaps localhost port numbers for stable .localhost URLs during development.

AI QA testing across web and mobile, run before each release.

Template for selling paid macOS apps with payments, licence keys and auto-updates already done.

The browser for ambitious web developers and designers.

Beautifully designed components you can copy and paste into apps.

Modern, responsive, pre-built blocks for marketing websites.