Meta System Design Interview Questions
Practice 1,159 real Meta interview questions for 2026. Covers top categories — Coding & Algorithms, Analytics & Experimentation, Data Manipulation (SQL/Python), Behavioral & Leadership, and System Design — across Software Engineer, Data Scientist, Machine Learning Engineer, Data Engineer, and Product Manager roles. Real questions from actual interviews with detailed solutions. Expect a software-engineering-heavy loop: timed algorithmic coding (trees, arrays, graph/maze problems, delimiter/CSV parsing), system-design prompts like leaderboards, flight search and online-judge architectures, and an increasingly common AI-assisted coding round that mirrors real workflows. Data Scientist rounds emphasize product analytics and experimentation—designing tests, diagnosing spend drops and bots, evaluating unconnected content, and writing SQL for multi-account, seller, and vehicle metrics. Machine Learning Engineer questions skew toward recommender and ranking work (place and friend recommendation, sparse-matrix ops, linear-regression derivations, newsfeed dislike models). Data Engineers focus on data modeling, ETL, capacity calculations, reservations/utilization queries, and production SQL/Python tasks. For interview preparation, prioritize timed coding practice, system-design templates, rigorous SQL drills (joins/CTEs/aggregation), clear A/B-testing frameworks, and concise STAR behavioral stories tied to measurable impact.
"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 experiment with network and novelty effects
This question evaluates a data scientist's competence in experimental design and causal inference under network interference and novelty effects, cove...
Choose metrics for fake-user classifier
Classifying Fake Accounts: Metrics, Capacity, Thresholding, and Validation Context - Population: 10,000,000 daily active users (DAU) - True fake rate ...
Resolve cross-team conflict and align incentives
Behavioral & Leadership: Cross-Team Conflict With Tight Timeline You are a Data Scientist interviewing for an onsite role. Describe a realistic cross-...
Learn complex topic fast under deadline
Behavioral Prompt: Rapid Ramp-Up on a New Analytical Framework You had to learn a new analytical framework in under a week to deliver a high-stakes re...
Estimate fake-account prevalence with capture-recapture
This question evaluates a data scientist's competency in capture–recapture estimation, estimation of population size with incomplete detections, stati...
How would you grow key product metrics?
This question evaluates product growth analytics and experimentation skills, including metric definition, funnel analysis, segmentation, hypothesis ge...
Compute Sliding Window Averages
This question evaluates proficiency in array manipulation, sliding-window techniques, and algorithmic efficiency including time and space complexity. ...
Solve four OA coding problems
This set of four problems evaluates core algorithmic competencies including array manipulation and counting in sorted arrays, resource-constrained opt...
Diagnose spend drops, bots, and Stories
This question evaluates a product data scientist's competencies in diagnostic product analytics, advertising measurement and attribution, bot and abus...
Implement BST Iterator and Ticket Queue
This question evaluates understanding of binary search tree traversal and iterator design with amortized time and space analysis, as well as dynamic p...
Find shortest path in a maze grid
This question evaluates proficiency in graph traversal and shortest-path reasoning on grid-based data structures, testing skills in pathfinding, state...
Find multi-account buckets and unread rate
You are analyzing a product in which one user can own multiple accounts. Use the following schema: Table: accounts - account_id BIGINT - user_id BIGIN...
Write SQL for Pixel Signal Metrics
You are working on Meta Ads Pixel analytics. Assume all timestamps are stored in UTC, and analyze the last 30 complete calendar days. Tables 1. advert...
Compute dot product of sparse vectors
This question evaluates proficiency with sparse data representations and algorithmic efficiency by requiring the dot product to be computed from lists...
Navigate unknown maze to find target
You are given an exploration interface for an unknown 2D maze that exposes only local actions (e.g., move(up/down/left/right) -> bool indicating succe...
Implement encoding validation and grid shortest path
Part A — Byte-encoding validation: You are given an array of integers in [0, 255] representing bytes. Determine whether the sequence encodes valid cha...
Solve grid path and top‑k frequency
Part A — Grid Reachability with Obstacles: Given an m×n matrix of 0s and 1s where 0 indicates a passable cell and 1 indicates a blocked cell, starting...
Implement merge-in-place and group cyclic-equivalent strings
You are given two ascending arrays to merge in place and a separate grouping task: Part A — In-place merge without known sizes: - Array A contains sor...
Compute top-N outgoing spenders
Add a feature to report the top N accounts by total outgoing payments across both immediate pays and scheduled payments. Implement: List<String> topNS...
Implement exponentiation and fill grid distances
This question evaluates algorithmic problem-solving skills in the Coding & Algorithms domain, specifically numeric algorithms for fast exponentiation ...