Software Engineer Interview Questions
Practice 4,360 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.
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"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."
Trace first pass of heap sort
Given the integer array [7, 6, 3, 5, 4, 1, 2], you apply heap sort to sort it in ascending order using a max-heap implementation. After building the i...
Design a Rolling Event Counter
Design an in-memory rolling event counter. The counter should support two operations: - record(timestamp): record one event at the given timestamp, me...
Design aggregator for multiple downstream services
Design a backend service for a large retailer (similar to Walmart) that must call many downstream services to fulfill a single user request. When a cl...
Count queen attacks on points with blockers
You are given positions on an (unbounded) 2D integer grid. - queens: coordinates of queens - points: query coordinates A queen attacks along 8 directi...
Check palindrome and find next larger palindrome
Problem: Palindrome Check + Next Larger Palindrome Part 1: Palindrome validation Given a string s, determine whether s is a palindrome (reads the same...
Identify the Extra Directed Edge
You are given a list of directed edges edges, where each edge is represented as [parent, child]. The graph contains nodes labeled from 1 to n, and it ...
Design an online ticket booking system
System Design: Online Ticket Booking System Design an online ticket booking system that allows users to discover events and book tickets. Assume the p...
Describe resolving conflict by persuading others
Describe a time you had a significant work-related conflict or disagreement with a teammate, stakeholder, or manager where you believed your approach ...
Sum numbers formed by root-to-leaf paths
You are given the root of a binary tree where each node contains a single digit from 0 to 9. Each root-to-leaf path represents a number obtained by co...
Design ticketing system with seat hold
Design an online ticketing system (similar to Ticketmaster) that allows users to browse events, select seats, and place a temporary 5-minute hold on s...
Design a news aggregation and feed service
Assume you are asked to design the backend for a news aggregation and feed service. Requirements: - The system pulls articles from multiple third-part...
Explain technical details of a past project
After you give a high-level overview of a recent project, the interviewer follows up with: > Can you walk me through the technical details of this pro...
Discuss experience with company products
In an interview with a company that develops infrastructure products (for example, Cloudflare), the interviewer asks: > Do you have any experience usi...
Compute longest increasing path in matrix
You are given an m x n grid (matrix) of integers grid, where m >= 1 and n >= 1. A path in the matrix is a sequence of cells where: - You may move from...
Compute party time blocks per neighborhood
You are given two datasets: 1. Parties: - party_id (string or integer) - start_timestamp (e.g., UNIX timestamp or datetime) - end_timestamp (...
Find user pairs with overlapping last K movies
You are given the same user movie-watching histories as in the previous problem. Each user’s history is an ordered list of movie IDs from earliest to ...
Improve robustness of graph cycle detection code
You have written code to detect cycles in a directed dependency graph of services, where nodes represent services and edges represent dependencies bet...
Detect cycle in directed dependency graph
You are given a directed dependency graph representing services in a system. - There are n services, labeled from 0 to n - 1. - You are given a list o...
Implement run-length encoding and decoding
You are given a string consisting of lowercase English letters. You need to implement run-length encoding (RLE) and its corresponding decoding. 1. Enc...
Describe a failed project and lessons learned
Describe a project you worked on that ultimately failed or did not meet its goals. Explain: - What the project was trying to achieve and your role. - ...