Data Scientist Interview Questions
Practice 2,964 real Data Scientist interview questions for 2026. Data Scientist interview questions drawn from Meta, Capital One, Amazon, Google, TikTok and similar employers — real questions from actual interviews with detailed solutions — designed to accelerate your interview preparation for product analytics, ML and production data roles. This collection emphasizes the practical skills interviewers test: SQL and data manipulation, experiment design and A/B testing, statistical reasoning, Python coding for data problems, model evaluation and feature engineering, plus machine-learning system tradeoffs and metric design. What’s distinctive about modern data-science loops is the blend of product thinking and reproducible ML: expect hands-on SQL tasks and funnel analysis in screens, deeper experiment-design and causality questions in mid rounds, and coding or modeling challenges plus ML-system discussions in senior loops. Interviewers evaluate problem framing, statistical rigor, and how you communicate decisions to product partners. To prepare, prioritize daily SQL practice (CTEs, window functions), refresh hypothesis-testing and power calculations, rehearse concise metric-driven narratives, and build a few end-to-end model or experiment stories you can explain clearly under time pressure.

"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."
Query departments and top earners
You are given three tables: 1. company - employee_id INT - first_name VARCHAR - last_name VARCHAR - department VARCHAR - salary DECIMAL...
Maximize profitable pairs
Maximize profitable pairs You are given an array profits of n integers representing net profit per item and an integer threshold T. You may form disjo...
Compute statistics in data stream
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Determine knights and knaves roles
Determine knights and knaves roles Knights and Knaves Logic Puzzle Context On an island, each person is either: - Knight: always tells the truth. - Kn...
Determine Metrics for Evaluating Homepage Recommendation Carousel
Determine Metrics for Evaluating Homepage Recommendation Carousel Experiment Evaluation: Homepage Recommendation Carousel Scenario A product team has ...
Analyze View Distribution and Recommendation Overlap in Videos
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Design a Controlled TV-Advertising Experiment for Sign-Ups
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Investigate Causes of Driver WOW Score Drop
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Choose Models for Imbalanced Data and Time-Series Forecasting
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Determine Impact of New Chat-Notification on User Engagement
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Investigate Declining ROI and Propose Effective Solutions
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Determine Optimal Marketing Budget Allocation for Maximum Profit
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Ensure Fairness Beyond Gender Parity in Lending Practices
Ensure Fairness Beyond Gender Parity in Lending Practices Fair Lending Behavioral Interview Prompt Scenario You are discussing fair lending practices ...
Diagnose Bias–Variance Trade-off in Supervised Learning
Diagnose Bias–Variance Trade-off in Supervised Learning Supervised Learning Review (Customer-Facing Ranking Context) You are designing and evaluating ...
Describe Your Professional Growth and Key Learning Experiences
Describe Your Professional Growth and Key Learning Experiences Behavioral Interview — Life Story: Growth and Readiness Scenario A 60-minute “life stor...
Analyze Change in App Metrics and Feature Impact
Analyze Change in App Metrics and Feature Impact Scenario A consumer app has either launched a new feature or observed a sudden change in a key metric...
Diagnose Decline in First Day Funding Rate
Diagnose Decline in First Day Funding Rate Diagnostic Case: First-Day Funding Rate Drop Context You are on a product analytics team monitoring onboard...
Explain Decision-Tree Training and Clustering Algorithms
Explain Decision-Tree Training and Clustering Algorithms Decision Trees and Clustering: Training Mechanics and Core Principles Context Technical/phone...
Design a Churn Model: Handle Missing Data and Justify
Design a Churn Model: Handle Missing Data and Justify Churn Prediction on Messy Subscription Data Context You are building a binary churn-prediction m...
Design Machine Learning Model for Facebook Groups Post Ranking
Design Machine Learning Model for Facebook Groups Post Ranking ML System Design: Ranking Facebook Groups Posts in News Feed Scenario You are designing...