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."
Determine equality of arbitrarily nested sets
Implement a function that determines whether two arbitrarily nested sets are equal. Sets are unordered and contain no duplicates; elements can be inte...
Sum palindrome-change costs over all substrings
This is a three-part coding screen. Each part is independent — a string-algorithms problem, a SQL aggregation problem, and a shell-parsing problem — a...
Design a Real-Time Monitoring System
Design a real-time monitoring system for a large production environment. The system should: - collect time-series metrics such as CPU, memory, request...
Compute minimum meeting rooms on circular day
Problem You are given a list of meetings scheduled within a 24-hour day. Time is cyclic: after 23:59 the next minute is 00:00. Each meeting is represe...
Flip a specific bit in an integer
Given a non-negative integer num and a zero-based bit position p, return the integer resulting from flipping only the bit at position p (i.e., 0 becom...
Find minimum tanks to cover all houses
You are given a string S representing a street: - 'H' = a house - '-' = an empty plot where you may place a water tank A house is considered covered (...
Outline the ML inference and labeling pipeline
Outline the ML inference and labeling pipeline Audio Detection System: ML Inference and Data Pipeline (Model Architecture Out of Scope) Context and As...
Design a URL Shortening Service
Design a production-ready URL shortening service. The system should: - Accept a long URL and return a short, unique alias. - Redirect a short URL to t...
Design a snapshotable key-value store
Design a snapshotable key-value store Design and implement a snapshotable key–value map supporting the following APIs: - S(key, value): set the curren...
Implement polynomial multiplication API in C
Problem Implement an API in C to multiply two polynomials. A polynomial is represented by its coefficients. You must define the input and output forma...
Design a multi-channel notification system
Design a notification system that receives alert events from other internal systems and notifies all subscribed users through multiple channels (e.g.,...
Answer feedback, conflict, and failure questions
Behavioral Questions Prepare structured answers (use STAR: Situation, Task, Action, Result) for: 1. Giving constructive feedback: Tell me about a time...
Design a low-latency trading platform
Design the architecture for a high-frequency fixed-income trading system. The platform should ingest live market data from multiple venues, maintain l...
Implement streaming RLE and bit-packed codec
You are implementing a simple compression scheme for sequences of 32‑bit signed integers. The codec should support two encoding strategies: 1. Run‑Len...
Why pursue full-stack engineering?
You are interviewing for a full-stack software engineering role. Explain why you are specifically interested in full-stack work instead of focusing on...
Populate next pointers in a perfect binary tree
You are given a perfect binary tree (all leaves at the same level; every internal node has two children). Each node has fields left, right, and next. ...
Design read-heavy org chart subordinate counts
You are given manager→direct-report relationships for an organization (an employee has at most one direct manager; the top-level employee has none). B...
Solve maze reachability and two follow-ups
You are given three independent coding tasks. 1) Maze reachability with “rolling ball” movement Given an m x n grid maze where 0 means empty and 1 mea...
Design a file search module like UNIX find
Design Task: Object-Oriented module that mimics UNIX find Context Design an object-oriented library that replicates the core functionality of the UNIX...
Solve numeric sequence pattern puzzles
Sequence Pattern Puzzles This is a timed pattern-recognition section of the kind used on quantitative-trading aptitude tests. You are given five indep...