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."
Design real-time driver heatmap system
System Design: Real-Time Driver Heatmap and Top-K Hottest Cells Context You are building a real-time driver heatmap for a ride-hailing platform that v...
Implement encryption and constant-time random set
You are asked about two coding topics from an onsite interview: 1. Key-based string encryption Briefly explain the idea of shared-secret encryption...
Validate whether a given sequence is a Hamiltonian path
You are given strArr, an array of three strings describing an undirected graph and a proposed vertex visit order: 1. strArr[0]: a comma-separated list...
Count Numbers Inside All Intervals
You are given: 1. An integer array nums. 2. A list of intervals intervals, where each interval is represented as [start, end]. The intervals are not s...
Implement a Versioned Key-Value Store
Design and implement an in-memory versioned key-value store. Requirements: - put(key, value, timestamp): store value for key at the given integer time...
Compute Earliest Completion Times
You are given n tasks numbered from 0 to n - 1. Each task i has a positive duration duration[i]. You are also given a list of prerequisite relationshi...
Reverse Nodes in K-Sized Groups
Given the head of a singly linked list and an integer k, reverse the nodes of the list in contiguous groups of size k. Requirements: - Only complete g...
Return nodes on a tree diameter path
Problem You are given an undirected tree with n nodes labeled 0..n-1 (connected, no cycles). The diameter of a tree is the longest simple path between...
Handle payment-service outages
You own a service that computes courier payouts and then submits payout requests to a downstream payment processor. What should your system do if the ...
Build a QuadTree From a Grid
Implement a compressed QuadTree for a square grid. You are given an n x n grid of values, where n is a power of two. The values are not limited to bin...
Build a simplified Wordle game in React
Problem: Implement a simplified Wordle in React Build a small Wordle-like game UI using React. Requirements - The game chooses a single answer word by...
Design a TinyURL-like short link service
Design a TinyURL-like service that generates short URLs and redirects users to the original long URLs. Requirements: - Provide APIs to create a short ...
Design a Checkers Game Simulator
Design and partially implement an object-oriented simulator for a two-player checkers-like board game. Requirements: - The game is played on an 8 x 8 ...
Design KV store with sliding-window QPS metrics
Problem Design an in-memory key–value store that supports basic operations and can report the average operation load over a recent time window. Functi...
Design a Merchant Ledger Service
Design a ledger service for a payments platform. The system must provide: - An API to record a transaction for a merchant. - An API to query the curre...
When to use a dictionary vs an array?
Question You’re implementing a feature and must choose between using an array/list or a dictionary/hash map to store and access data. Explain when you...
Build a Flexible Expense Rules Engine
You are building a rules engine for a corporate credit card product. Employees use company cards for business expenses, and managers define policies t...
Design sequential reveal classification and policy
FashionMNIST: Row-wise Reveal Evaluation, Reward-Optimal Masking, Augmentation, and Early Exit Context You have a trained CNN classifier for FashionMN...
Design a local activity counter service
System Design: Near-Real-Time Activity Counting Service Context Build a service that ingests high-throughput client events and provides near-real-time...
Design a concurrent web crawler
Question Design and implement a concurrent web crawler. Starting from one or more seed URLs, the crawler should fetch pages, extract links, deduplicat...