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 a payment processing system
Scenario Design a backend payment system for an online product that supports: - One-time charges and refunds. - Idempotent payment APIs (clients may r...
Process document edit events
Implement a line-based document editor. You are given: - an initial document represented as an array of strings, where each string is one line - a lis...
Describe a proud project and handling credit conflict
Answer the following behavioral questions: 1. Project you’re proud of: Describe a project you’re proud of. Explain what you built, your role, the impa...
Search Book Titles
You are given a list of book titles and a user query string. Return all titles that are relevant to the query. A title is considered relevant if any t...
Compute ring window max and deletion indices
Part A — Ring window maximum: You are given n computers arranged in a circle, represented by an array of bits (1 = on, 0 = off), and an integer k (1 <...
Build a Heart Disease Baseline
You are given a tabular dataset for predicting whether a patient has heart disease. The dataset contains a binary target column such as has_heart_dise...
Describe Your Most Complex Project
The behavioral rounds focused on two areas: 1. Describe the most complex project you have worked on. Expect deep follow-up questions about: - the busi...
Contrast processes and threads
What are the differences between processes and threads? Compare memory isolation, resource ownership, scheduling, context-switch cost, inter-process c...
Design a scalable URL shortener with expiration and security
System Design: URL Shortening Service at Internet Scale You are asked to design a URL shortening service for hundreds of millions of users with high a...
Troubleshoot CPU, latency, and DNS issues
A) A Linux server’s CPU usage suddenly spikes. What immediate checks and commands would you run (e.g., top/htop, pidstat, perf, iostat), how would you...
Simulate robot path and detect boundedness
A robot starts at (0, 0) facing north on an infinite 2D plane. It executes a command string s consisting of 'G' (move forward one unit), 'L' (turn lef...
Design a profiling plan for kernels
Rigorous Profiling and Experimentation Plan for a Kernel Simulator You are given only a kernel simulator that reports cycle counts and microarchitectu...
Walk through a recent project design
System Design: End-to-End Project Walkthrough Provide a structured walkthrough of a recent project you led end-to-end. Organize your answer using the ...
Design relational-to-NoSQL migration pipeline
System Design: Migrate From Relational DB to a NoSQL Key-Value Store with Snapshot + CDC Context You need to migrate data from an OLTP relational data...
Design cloud storage with quotas and compression
System Design: Multi‑Tenant Cloud Storage Service (Take‑Home) You are tasked with designing a multi‑tenant cloud storage service that supports file up...
Group words into anagram lists
Given an array of strings, group the words into lists of anagrams and return the collection of groups in any order. For example, ["abc", "cab", "edf"]...
Design auth, session security, and top-N users
Web App Design: Authentication, Security, and Top-N Active Users Context: Build a browser-based web application where a user signs in and the page dis...
Implement multi-part cost calculator
You are given a price catalog and a list of orders. Implement the following in any language (Python examples acceptable): Inputs - price_catalog: mapp...
Compute Differences Between Catalog Trees
You are given two rooted catalog trees. Each node has a unique string key among its siblings and an associated value. Compare the two trees and return...
Design consistent hashing for sharding
Design a Consistent-Hashing Router with Replication You are building a stateless router that maps arbitrary keys (for example, request IDs or cache ke...