Free3,500+ developers16 challenges available

Practice frontend
machine coding
interviews.

Learn the concepts, then build from scratch. Each challenge comes with a deep-dive tutorial and a hands-on practice environment.

How it works

Learn, then build.

📖
01

Read the tutorial

Each challenge has a detailed learn page covering concepts, architecture, code walkthroughs, and interview Q&A.

🛠️
02

Build from scratch

Jump into the practice page with a basic setup ready. The data and UI shell are there — you write the logic.

🎯
03

Nail the interview

Understand the why behind every pattern. Each tutorial ends with common follow-up questions interviewers ask.

Challenges

Pick a challenge and start coding.

Skeleton Loader

Easy

Build a skeleton loader that shows animated placeholder shapes while a user profile card loads.

ReactCSS AnimationLoading StatesUX

Live Markdown Editor

Hard

Build a split-pane markdown editor with real-time preview. Write your own markdown-to-HTML parser — no libraries.

ReactRegexString ParsingSplit Pane

Autocomplete / Typeahead

Medium

Build an autocomplete input with debounced API calls, keyboard navigation, and highlighted matching text.

ReactDebounceKeyboard NavAccessibility

Server-Side Todo App

Easy

Build a full-stack todo app with server-side rendering, API routes, and client-side interactivity.

ReactNext.jsCRUDAPI Routes

Custom Debounce

Easy

Implement a debounce function from scratch and wire it to a search input with an event log.

ReactClosuresTimers

Infinite Scroll

Medium

Build an infinite scroll feed using IntersectionObserver with a paginated API.

ReactIntersectionObserverPagination

Testimonials

Loved by developers worldwide.

Join 3,500+ developers who use Event Looped to prepare for frontend interviews.

PS

Priya S.

Frontend Engineer @ Startup

The learn-then-build approach is exactly what I needed. I went from struggling with machine coding rounds to clearing 3 out of 4 interviews.

GS

Gaurav Sharma

Senior Developer

The deep-dive tutorials are better than most paid courses. The interview Q&A sections alone are worth it — helped me answer follow-ups I'd never thought of.

RM

Rahul M.

Full Stack Developer

I practiced the todo and infinite scroll challenges the night before my interview. Both came up almost exactly. Landed the offer the next week.

SL

Sarah L.

Frontend Lead

I recommend this to every junior dev on my team. The code quality in the solutions is production-grade, not just interview-grade.

DP

Dev Prajapati

React Developer

The virtualized list and OTP challenges were tricky but the tutorials broke them down perfectly. Felt confident building them from scratch after.

SY

Shivani Yadav

Software Engineer

Clean code, real patterns, no fluff. This is how interview prep should be. I use it to warm up before every frontend interview loop.

Built for developers, by developers. Happy coding! 🚀