CodePen
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CodePen BuiltWithA great tool to help you discover the technology being used by a variety of websites. I was impressed that upon signing up that I had full access to a free list of leads.
Based on our record, CodePen should be more popular than BuiltWith. It has been mentiond 511 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Embed on DEV: If you prefer CodePen embed, create a Pen with that HTML and add to the post as: {% codepen https://codepen.io//pen/ %}. - Source: dev.to / 8 months ago
CodePen is where creativity meets frontend code. You can write HTML, CSS, and JavaScript and see results instantly in the browser. - Source: dev.to / 11 months ago
For those preferring agent-based approaches, Replit Agent shines. Khris Steven, Founder of KhrisDigital Marketing, notes, "You can simply describe what you want your app to do in plain English, and Replit Agent will generate the code and deploy it." This natural language interface fosters collaboration, turning ideas into deployable apps in minutes. - Source: dev.to / 11 months ago
After wrapping everything up, I hosted the final toggle on CodePen so others could test it out and learn from the approach. What started as a simple idea became a complete, responsive, and accessible component, thanks to a process that blended creativity with automation. - Source: dev.to / 11 months ago
For this CSS Art challenge, I wanted to step out of my comfort zone. While I've used CSS extensively for web apps and websites, I had never built an art piece purely with CSS. I started by diving into codepen and other inspiration sites, getting a feel for what was possible. Eventually, a rough sketch of an office atmosphere in Excalidraw became my guiding vision. My goal was to depict a typical office scene,... - Source: dev.to / 11 months ago
Evan You, creator of Vue.js, is a prime example. Vivek Nair, Co-Founder of BotGauge, notes that You โcreated something that addresses real developer needs with clean logic and thoughtful design.โ Vue.js powers over 1.5 million websites in 2025, a testament to its scalability and developer trust, as reported by BuiltWith. Youโs ability to build a framework independently, without corporate backing, underscores his... - Source: dev.to / about 1 year ago
There exist websites like https://builtwith.com so answer to your question is yes. - Source: Hacker News / over 1 year ago
BuiltWith says the web client is NextJS which is interesting as ChatGPT made a big switch away to Remix IIRC. https://builtwith.com/?https%3a%2f%2fclaude.ai%2fnew. - Source: Hacker News / over 1 year ago
Also, wow that is an obsene amount of libraries they use: https://builtwith.com/?https%3a%2f%2fspectrum.ieee.org%2fdisney-robot-2668135204. - Source: Hacker News / about 2 years ago
I would say run both sites through https://builtwith.com/ to get what all they used in the building process. Source: over 2 years ago
JSFiddle - Test your JavaScript, CSS, HTML or CoffeeScript online with JSFiddle code editor.
Wappalyzer - Wappalyzer is a technology profilers and leads data provider. Create lists of websites and contacts that use certain technologies.
CodeSandbox - Online playground for React
WhatRuns - Extension that helps you identify technologies used on any website at the click of a button.
GitHub - Originally founded as a project to simplify sharing code, GitHub has grown into an application used by over a million people to store over two million code repositories, making GitHub the largest code host in the world.
Elucify - A completely free software tool that uses crowdsourced data to find business email addresses