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."
Root-cause an incident and drive consensus
Root-Cause Plan: Sudden Drop in Voice Checkout Conversion (Alexa Shopping) You are informed that the "voice checkout conversion" KPI for Alexa Shoppin...
Demonstrate Leadership in Ambiguous Analytics Projects
Behavioral & Leadership: End-to-End Analytics Project Under Ambiguity and Time Pressure Context You are a Data Scientist interviewing for a technical ...
Write SQL and Pandas for Uber Trips
Assume 'today' = 2025-09-01. You are given the following schema and small ASCII samples. Tables - riders(rider_id, name, signup_date) - drivers(driver...
Design an A/B test for ML model launch
Feed Ranker A/B Test Design and Powering You are replacing the current ranker with a new model in a feed. Baseline CTR is 2.0%. You expect a +5% relat...
Evaluate channels and allocate budget
Marketing Analytics Case: Funnel, Attribution, Budget Optimization, and Incrementality You are given a daily-by-channel dataset with the following col...
Analyze aggregator lender page flows
Loan Comparison Page: Instrumentation, Metrics, Insights, Experiment, and Cannibalization Context You own a loan comparison page (similar to NerdWalle...
Design email to avoid Promotions without online tests
Offline Design of a Transactional Email to Minimize Promotions/Spam Classification Context You must finalize the design of a single in‑game transactio...
Implement PAVA spend-smoothing under no-borrowing constraint
Monotone Spending Plan via Isotonic L2 Regression (No-Borrowing) Context: You observe yearly discretionary income profit[1..65] (nonnegative reals) an...
Explain why join C1 and your impact
Why Capital One (C1)? Behavioral/Leadership Prompt for a Data Scientist Task Provide a concise, evidence-based answer that: 1. Gives 2–3 specific, ver...
Prevent data registration outage and reduce loss
Preventing Silent Failures in the Premium Registration Pipeline Context A premium registration pipeline silently failed for three months, causing thou...
Explain a non-linear industry switch
Behavioral Interview Prompt — Transition from Semiconductor to SaaS Analytics You are in an HR screen for a Data Scientist role. The interviewer chall...
Design an ETA experiment under interference
Experiment Design: Estimating Causal Impact of a New Rider ETA Model in a Two-Sided Marketplace Context You are testing a new rider ETA model that cha...
Compute conditional occupancy across two rooms
Probability and Bayes Update: Two Rooms Setup There are two rooms. Prior over occupancy states: - With probability 1/3: both rooms are occupied. - Wit...
Quantify database bug cost/benefit
Bug Impact on Commission and Admin Costs (Jan–Mar) Context and Assumptions - The company earns commission revenue on user spend; an admin fee is a com...
Find premium share for break-even
Break-even Mix of Regular vs Premium Customers You are evaluating a two-tier customer model with a fixed total of 2,000,000 customers. Find how many m...
Compute current annual profit
Loyalty Program Profitability Calculation A loyalty program has 2,000,000 customers. Revenue per customer (per year): - Annual membership fee: $50 - C...
Design profitability growth plan
Case: Growing Profitability for a Grocery Loyalty-Card Business You are advising a grocery loyalty-card business that wants to grow profitability. Tas...
Describe best team and complex project
Behavioral & Technical Deep-Dive Part 1 — Best Team You Worked On Describe a high-performing team you were part of. Include: 1. Mission and business i...
Write SQL and pandas for shopping events
Use the schema and sample data below to answer SQL and pandas tasks. Treat 'today' as 2025-09-01. Schema users(user_id INT, country STRING) pins(pin_i...
Diagnose a 20% retail revenue drop
E-commerce Revenue Drop Diagnosis Case Context Week T net revenue is down 20% versus the prior 4-week moving-average baseline. You have weekly e-comme...