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."
Implement buffered file writer with concurrency support
You are given a simple file writer class that writes data directly to disk: `cpp class FileWriter { public: // Append data to the file on disk imm...
Implement core puzzle/array/grid routines
You may be asked to solve one or more of the following coding exercises (write clean, testable code; discuss time/space complexity): 1) Jigsaw assembl...
Implement string formatting and request tracking tasks
You are given several small coding tasks. Implement each as described. Task A — Convert snake_case to camelCase Write a function that converts an iden...
Find Shortest Grid Path
You are given an m x n grid where 0 represents an open cell and 1 represents a blocked cell. You are also given a start cell (sr, sc) and a target cel...
Implement and Debug Backprop in NumPy
Two-Layer Neural Network: Backpropagation and Gradient Check (NumPy) You are implementing a fully connected two-layer neural network for multi-class c...
Design a concurrent web crawler
System Design: Concurrent Web Crawler (Threads) Design and implement a basic web crawler that fetches pages concurrently using a thread executor (e.g....
Implement Employee Validation and Snake
This interview covered two coding tasks: 1. Employee validation - Implement a function that validates a collection of employees against a set of bu...
Describe your most impactful project
Tell me about the project where you had the most impact. Explain the business or user problem, why it mattered, what your specific role was, the harde...
Maximize Boxes Stored Through One Entrance
You are given two integer arrays: - boxes[i]: the height of the i-th box. - rooms[j]: the height limit of the j-th room in a linear warehouse. The war...
Design a Hotel Booking System
Design the backend for an online hotel booking platform. The system should let users: - search for hotels by location, dates, and number of guests - v...
Design a Library Management System (API and Schema)
Design the API and database schema for a library management system. The library lends physical books to registered members. Members can search the cat...
Implement a Byte Pair Encoding (BPE) Tokenizer
Implement a Byte Pair Encoding (BPE) Tokenizer Byte Pair Encoding (BPE) is a tokenization algorithm widely used to build the vocabularies of modern la...
Design a Distributed Metrics Counter
Design a distributed metrics counter service for internal product telemetry. The service should support: - increment(metric_name, delta, tags, timesta...
Design an extensible expense rule evaluator
Scenario You are building a corporate employee expense card product. Admins define policies (“rules”) to prevent misuse and to flag policy violations....
Validate password and list rule violations
Problem You are given a password string p. Validate it against a set of rules and return all rules that the password violates. Rules 1. Length must be...
Design a jigsaw puzzle (OOD)
Object-Oriented Design: Jigsaw Puzzle Design an object-oriented model for a jigsaw puzzle game. Requirements - The puzzle consists of a set of pieces ...
Design a typeahead search service
Design a search autocomplete system for a large application. As a user types a prefix, the system should return relevant suggestions with low latency....
Find Common Prefix Across Strings
Given an array of strings, return the longest string prefix that is shared by every string in the array. A prefix must start at index 0 of each string...
Design an AI playground editor
Design a full-stack AI playground web application similar to a chat product, but with one document-like component that interleaves user prompts and mo...
Model data for an ads platform
Design a data model (logical schema) for an advertising platform. Include core entities such as: - Business/account (advertiser) - Campaign and budget...