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."
How would you build UberEats ranking?
UberEats wants to improve its recommendation or ranking system for restaurants shown to users on the home feed or in search results. Design the machin...
Handle scope creep and teammate conflict
Behavioral & Leadership Two-Part Prompt (Data Scientist — Technical Screen) You will answer two behavioral prompts relevant to a data scientist role. ...
Explain helping-others trade-offs with evidence
Describe a specific situation where you proactively helped others at work despite conflicting priorities. Include: a) your objective and stakeholders;...
Write SQL for video-call recipients and FR activity
Given the schema and samples below, write ANSI‑SQL to answer both questions. Assume dates are stored in UTC. Today is 2025-09-01, so “yesterday” is 20...
Write SQL/pandas for KPI anomaly
Write SQL (and outline equivalent pandas) for a KPI anomaly investigation. Assume today = '2025-09-01'. Schema: Users(user_id INT, country TEXT, signu...
Choose target customers and define success metrics
Stripe plans to launch “Instant Payouts+” for SMBs. How would you choose initial target customers and measure success? - Targeting: Propose a scoring ...
Analyze an A/B test over last 7 days
A/B Test Readout and Decision (2025-08-26 to 2025-09-01) Context A 50/50 A/B experiment on the checkout flow ran for 7 days, from 2025-08-26 through 2...
Solve two-sum variants at scale
Base task: Given nums = [3, 1, 2, 2, 4] and target = 4, return the 0-based index pair (i, j) with i < j such that nums[i] + nums[j] = target. If multi...
Design cloud product packaging and pricing strategy
Cloud-Service Pricing and Packaging Case Context You are the first PM at a cloud-service startup that is functionally at parity with competitors but h...
Present a project to non-technical leaders
10–15 Minute Modeling Project Presentation (Mixed Stakeholders) Task Prepare a 10–15 minute presentation of a past modeling project for a mixed audien...
Write left-join queries with tricky filters
Assume 'today' = '2025-09-01'. Do NOT use window functions (e.g., RANK). Use LEFT JOIN, COUNT(DISTINCT), GROUP BY, HAVING as appropriate. Schema: - us...
Compare Normal vs Poisson; test dispersion and approximate tails
You collect n=200 independent minute-level event counts with sample mean x̄=14.5 and sample variance s²=16.2. 1) Under a Poisson(λ) model, derive the ...
Contrast UI vs backend testing; design UI-change test cases
Part A — Differentiate UI vs backend testing: For a single-page web app backed by a BFF (backend-for-frontend) that calls a payment API, explain preci...
Design navigation-safety simulation parameters and experiments
You must design a simulation-based evaluation for navigation safety of an autonomous agent. Be specific: a) Enumerate scene parameters to vary and jus...
Handle unresponsive stakeholders and align metrics
You have 45 minutes, two interviewers are minimally responsive, and the problem statement is vague. Walk through how you will proactively drive clarit...
Design analysis to validate reported decline
A beverage company claims 'Q2 sales dropped' but gives you only one dataset (the transactions table described above) and 45 minutes. Design the analys...
Deploy multi-armed bandits safely
Online bandit with 3 variants, churn guardrail, and delayed conversions Context You are running an online experiment with 3 variants (including contro...
Design a robust conversion propensity model
Daily Notification Propensity Model (Top-20% Targeting) Context You need to score users once per day with the probability they will make a purchase wi...
Diagnose coffee-shop profit decline
You run a single-location coffee shop. In August 2025, profit dropped 18% vs July while transactions fell 4% and average check rose 2%. You have these...
Design video-ads experiment and handle null results
You are launching a new video-ad format. Design an end-to-end A/B test to evaluate it against the current ad format. Be precise: 1) Define exposure an...