Frontend Engineer Interview Questions
Practice 55 real Frontend Engineer interview questions for 2026 — real interview questions from actual interviews with detailed solutions. This collection targets Frontend Engineer interview questions and practical interview preparation across companies currently hiring heavily for frontend talent, including Toma, Uber, Coinbase, and Robinhood. Expect live React/TypeScript coding, component-level problems, and end-to-end tasks that prove you can ship resilient UI under constraints. What makes frontend loops distinctive is their emphasis on product-quality engineering: component design and state management, DOM and asynchronous behavior, and performance/accessibility under load. At Uber interviews you’ll see DOM-manipulation and async-pattern scenarios and large-scale UI performance tradeoffs; Coinbase favors pixel-perfect implementations, robust form/state synchronization, and edge-case handling; Robinhood tests real-time UI consistency and performance at scale; Toma and other early-stage teams focus on rapid prototyping and full-stack integration. Prep by building expressive, testable components, mastering React patterns and TypeScript typings, profiling and accessibility checks, and rehearsing clear trade-off explanations for design decisions.
"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"
"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"
"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."
"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."
"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."
"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."
"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."
"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."
"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."
"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."
"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."
"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."
"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."
"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Design Calendar Frontend State for Recurring Events
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Design a Performant Frontend News Feed
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Build Six Hold-to-Play Piano Keys with Vanilla Web APIs
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Build an Arrow-Controlled Kanban Board in React
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Build a Wordle-Style Game in React
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Implement an Accessible Autocomplete Search Component
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Design a Collaborative Playlist Editor
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Build a Chainable Rectangle Manipulation API
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Build a Configurable Two-Player Tic-Tac-Toe Board in React
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Build a Virtualized React Spreadsheet with Cell Formulas
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Design a ChatGPT Playground
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Design a Reusable Dropdown Menu Component
This question assesses a candidate's ability to design a reusable, production-grade UI component, covering public API design, controlled versus uncont...
Explain JavaScript Scope, Closures, Timers, and the Event Loop
Explain JavaScript Scope, Closures, Timers, and the Event Loop Answer the following JavaScript runtime questions precisely. Distinguish the language e...
Build an Accessible Recursive Expand-and-Collapse Tree in React
Build an Accessible Recursive Expand-and-Collapse Tree in React Implement a React component that renders hierarchical data with + and - controls for c...
Diagnose Cold-Load and Massive-Table Performance in a Web App
Diagnose Cold-Load and Massive-Table Performance in a Web App You are reviewing two frontend performance problems. Explain how you would measure each ...
Run Promise Tasks with Bounded Concurrency
Run Promise Tasks with Bounded Concurrency The source reports a pure TypeScript or JavaScript coding round involving Promises, but it does not preserv...
Navigate a Tight Deadline and an Ambiguous Engineering Project
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Build a Debounced Autocomplete Search Bar
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