Software Engineer Interview Questions
Practice 4,229 real Software Engineer interview questions for 2026 — real questions from actual interviews with detailed solutions to speed your interview preparation. This collection reflects what top tech firms like Meta, Amazon, Google, DoorDash, and TikTok typically evaluate: rigorous coding and algorithmic problem solving, increasing expectations for end-to-end system design (including GenAI/LLM design at some teams), clear complexity analysis, and reliable engineering judgment under constraints. Expect a multi-stage pipeline: recruiter screen, timed or asynchronous coding assessments, one-to-more live coding rounds focused on data structures and correctness, system-design conversations for mid and senior levels, and behavioral/hiring-manager interviews that probe ownership and collaboration. To prepare, prioritize patterned practice (timed mock interviews and implementation + optimization), learn scalable design frameworks, rehearse concise trade-off communication, and tailor examples to company signals like Amazon’s leadership lens or product/latency focus at delivery and media-driven teams. Consistent, feedback-driven practice that combines problem-solving speed, clean code, and measured design reasoning is the quickest path to offers.
"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."
Compute triangle min path and dice stopping stats
You are given two independent interview questions. 1) Triangle minimum path sum (DP) Given a triangular array triangle with n rows, find the minimum p...
Describe your most challenging project and leadership
Describe the most challenging project you have worked on. Your interviewer will drill into details such as: - What the project goal and constraints we...
Compare WebSocket, SSE, and long polling
You are building real-time features for a web application and the interviewer probes your networking fundamentals across several layers of the stack. ...
Navigate conflict, difficult people, and culture issues
Answer the following behavioral questions with clear examples (preferably using the STAR method: Situation, Task, Action, Result). Be explicit about y...
Solve four classic algorithm problems
You are given four independent coding tasks. For each task, implement the required function. --- Problem 1: Zigzag level-order traversal of a binary t...
Design a replicated key-value store with quorums
Design a distributed system that replicates key–value pairs across multiple replicas. The interviewer wants to focus on replication, quorums, and fail...
Implement log aggregation in React
React Coding: Log stream aggregation You are building a small React feature that displays real-time statistics from a log stream. Log event format Eac...
Explain HashMap Resizing Without Long Pauses
Explain how a hash map works internally. Cover how keys are mapped to buckets, how collisions are handled, and when the table decides to resize. Follo...
Simulate pouring water onto terrain
Problem You are given an integer array heights representing a 1D terrain (each index is a column height), an integer V (units of water), and an index ...
Implement sequential and parallel URL requests
You are given a list of URL strings. For each URL, send an HTTP GET request and return the responses. Output format Return a list of objects: - url: t...
Choose fastest transportation mode on city grid
You live in a city modeled as a 2D grid. Each cell is either: - A transportation mode 1..4 where: - 1 = Walk, 2 = Bike, 3 = Car, 4 = Train - S = sou...
Count visible people to the right
Problem You are given an array heights of length n, where heights[i] is the height of the i-th person standing in a line from left to right. For each ...
Count changed nodes between two menu trees
You maintain a merchant menu as a rooted tree. Each node represents a menu item/category and has: - key (string, unique among siblings) - value (integ...
Design Real-Time Auctions for Social Posts
Design a real-time auction feature for a large social photo and video app. A creator can attach an auction to a post. Viewers can place bids, and ever...
Design a feedback-text personalization data system
System/ML design scenario: personalize using user feedback text You are building an embeddings + personalization pipeline for a consumer product (e.g....
Design a simulator to replay left-turn videos
Design a system to simulate and replay a car’s left-turn driving scenario using recorded video. The replay should support browsing a specific left-tur...
Design a distributed rate limiter service
Scenario You need to design a rate limiting system that can be used by multiple API gateways and/or many backend services (not just embedded in a sing...
Solve string and hashmap coding tasks
You will solve the following coding tasks (independent of each other). Provide clear input/output behavior and handle edge cases. 1) Longest non-repea...
Implement idempotent request handling with idempotency keys
Problem You are implementing an API endpoint (e.g., POST /charge) that must be idempotent using an Idempotency-Key. Design and implement an in-memory ...
Design a live video comments system
System Design: Live Video Comments (FB Live-style) Design a system that supports real-time comments for a live video stream. Core user experience - Vi...