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."
Diagnose and fix flawed model fit
Fixing a Churn Classifier: Encoding, Imbalance, Evaluation, and Fairness Context You inherit a binary classifier that predicts churn=1. The current im...
Explain life-story choices and pre-read insights
HR Screen Pre‑read and Life Story Exercise (Data Scientist) Context You receive a 6‑page HR pre‑read 24 hours before a 60‑minute "Life Story" intervie...
Diagnose drop and assess metric change impact
Investigate a Drop in Average Posts per DAU Context You work on a large consumer social app. The metric "average number of posts per DAU" (daily activ...
Differentiate x^x and analyze domain
Compute the derivative of f(x) = x^x for x > 0 using logarithmic differentiation. State precisely the domain where the derivative is real-valued. Eval...
Show ownership in ambiguous creator-growth work
Describe a time you owned an ambiguous growth problem for creators end‑to‑end. Pick one project and cover: 1) the exact business goal and why it matte...
Design a creator posting-frequency experiment
You’re on the Creator Growth (PGC) team of a short‑video platform. Product proposes a push/email nudge expected to raise creators’ weekly posting freq...
Write SQL to compute shop visibility share
Assume today is 2025-09-01. Compute the top 3 shops by average daily visibility share over the last 7 days (2025-08-26 to 2025-09-01, inclusive) for U...
Demonstrate concise leadership
You receive feedback that in case interviews you ask many clarifying questions, take a few seconds before answering, and your answers are not concrete...
Build and validate a binary classifier
ML Pipeline with Grouped CV, Imbalance Handling, Calibration, and Thresholding Context: You have a labeled dataset where the target is is_active_30d (...
Explain AUC, imbalance, losses, and networks
Imbalanced Classification & Regression: ROC/PR, Losses, and Training Strategies You are evaluating a binary classifier and a regression head in a mach...
Reduce overfitting under constraints
Reduce Overfitting Under Latency Constraints (Tabular Regression) Context (assumed) - You have a tabular regression model with a large generalization ...
Estimate revenue of organic shopping tab
Estimate Monthly Revenue for a New Shopping Tab (Organic Only) Context You are evaluating the potential monthly revenue impact of launching a new Shop...
Diagnose and fix linear regression assumption breaks
OLS Assumptions, Diagnostics, Remedies, and Refitting Under Heteroskedasticity and Multicollinearity You are fitting a linear regression with Ordinary...
Design an A/B test for WhatsApp call reliability
A/B Test Design: Adaptive Codec for Unstable Networks (WhatsApp Calling) Context You join the Calling organization. A PM proposes enabling an adaptive...
Analyze skewed comments and sampling effects
Right‑Skewed Daily Comments: Location Stats and Sampling Distributions You’re analyzing daily user comments per user, which are right‑skewed count dat...
Design experiment on culture memo emphasis
A/B Test Design: Prominently Feature the Culture Memo on Job Description Pages You are designing an experiment to evaluate whether prominently featuri...
Build an uplift model for targeting
Flu-shot Campaign: Treatment-Effect Modeling and Targeting Policy You have historical campaign logs from last season that include randomized holdouts....
Decide and justify product metrics amid trade-offs
Smart Sort Feed Ranking: Metrics, Experiment, Decisions, and Monitoring Context: You are introducing a new Smart Sort ranking for a content feed. It s...
Prove conversion ads value via incrementality
Measuring Incremental Lift of Conversion-Optimized Ads Context An e-commerce advertiser is running conversion-optimized ads and requests rigorous proo...
Prioritize six improvements for a favorite app
Case Prompt: Product Thinking, Modeling, and Experimentation Choose one consumer mobile app you personally use weekly. 1. Propose exactly six concrete...