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 User Sessionization From Event Stream
You are building a backend data-processing component that consumes a stream of newline-delimited JSON events. Each event represents a user sending a m...
Design a pizza ordering system
Design the core object-oriented model for a pizza ordering system used by a small restaurant. The system should allow customers to: - browse a menu of...
Implement Luhn-based card validation and inference
Question Implement a set of utilities for credit-card validation and inference using the Luhn checksum algorithm and standard brand patterns. Brand pa...
Cross-reference logs to flag spam numbers
You are given two data sets: ( 1) a call log containing phone numbers observed in calls and ( 2) a list of user reports where each entry is a phone nu...
Implement a min-heap column allocator
You are given an integer k (number of columns) and an array posts of positive integers where posts[i] is the height of the i-th post. All columns star...
Design JSON serialization for circular references
Design a JSON Serialization/Deserialization Strategy With Cycles and Determinism You are designing a JSON-based serializer/deserializer for a graph of...
Present project and answer behaviorals
Behavioral & Leadership Project Presentation (Software Engineer) You are interviewing onsite for a Software Engineer role. Prepare a slide-style narra...
Design autonomous cloud monitoring and remediation
Design an AI-Assisted Monitoring and Auto-Remediation Service Context Design a service that monitors cloud applications across multiple providers, col...
Implement retry wrapper and interdependent validators
Context You are implementing reusable utilities that are commonly needed in modern web apps: 1) a robust retry wrapper for functions that can fail syn...
Explain project scope, timeline, and delegation
10–15 Minute Project Deep Dive (Behavioral and Leadership in a Technical Screen) Context You are asked to present a concise, slide-driven deep dive on...
Implement a Worker Hours Register
Implement an in-memory WorkHoursRegister system for contract workers. The system tracks office entry and exit events, completed work time, promotions,...
Design a Twitter hashtag metrics aggregator
System Design: Hashtag Metrics Aggregator Design a service that ingests a high-volume stream of social posts (like tweets) and produces metrics/aggreg...
Detect recurring transactions from a ledger
You are given a list of credit/debit card transactions. Each transaction has: - transaction_date (YYYY-MM-DD) - merchant (string) - amount (decimal, p...
Implement an LFU cache
Problem: LFU Cache Design and implement a Least Frequently Used (LFU) cache with a fixed capacity. The cache supports the following operations: - get(...
Design a fair event registration queue API
Scenario Design an in-memory service (OOD-style) to manage registrations for an event where fairness means users are served strictly in the order they...
Implement binary encode/decode with frequency tree
Problem Implement a binary encoding and decoding scheme for strings based on character frequencies (Huffman-like coding). You must implement two funct...
Decide and implement DP/heap and approximation
You have 90 minutes to complete three related coding tasks: a) Dynamic programming: Given an integer array nums (n ≤ 2e 5) and a threshold T, design a...
Whiteboard and Deep Dive a Past Project
System Design: End-to-End Architecture Walkthrough Prompt Whiteboard the end-to-end architecture of a complex, user-facing system you led. Cover: 1. M...
Enable secure offline reservation caching
System Design: Offline Caching for Reservations (PWA) Design a web application that supports offline access to reservation information. The app is a p...
Minimize Operations to Balance Shipments
A shop has n item types, where quantity[i] is the positive integer quantity of the i-th item type. The item types must be shipped in two non-empty con...