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."
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-...
Reflect on interview takeaways and adaptation
Behavioral Reflection: Multi‑Round Interview Adaptation (Data Scientist, HR Screen) Context You recently completed a multi‑round interview process for...
Critique a product interface and propose fixes
Product Thinking: Heuristics, Accessibility, Redesign, and Validation Prompt Pick one digital product you use daily (web or mobile). Identify: - One s...
Merge ad CSVs and compute CTR
Using SQL, clean and merge four CSVs and answer all parts exactly. Schema and sample rows (assume types: date is DATE, others INT/VARCHAR): platforms(...
Identify and validate risky assumptions
Vegan Burger Business Case: Validate Risky Assumptions You are evaluating whether to launch a new vegan burger across a multi-store quick-service chai...
Design and justify unread-account pinning experiment
Experiment: Pin Unread Accounts at the Top of the Account Switcher You plan to launch a UI change for people who own multiple accounts: pin accounts w...
Implement K-means and run two iterations
Given points P={(0,0),(0,2),(2,0),(2,2),(8,8),(8,10),(10,8),(10,10)} and k=2, (1) initialize centroids with k-means++ using seed=42 and Euclidean dist...
Choose linear regression or decision tree appropriately
Choose Between Linear Regression and a Decision Tree Under a Hinge and Interaction DGP Context You have 100,000 i.i.d. observations with features x1 (...
Contrast LSTM and Transformer for long sequences
Train a Long-Context Autoregressive LM (T = 8192, H = 512, B = 8) You are training an autoregressive language model with: - Sequence length T = 8192 t...
Demonstrate cultural fit and sales-oriented leadership
Context You are interviewing for a technical, customer-facing Data Scientist role at NVIDIA (HR screen). Provide concise, business-outcome-oriented re...
Implement Director awards with Python OOP
Python OOP Exercise: Director extends Cast Context You are working with a simple class hierarchy where Director extends Cast. Implement a robust, test...
Use DiD for staggered treatment adoption
Staggered DiD for a Weekly RPU Rollout (50 Regions, 2025-06-01 to 2025-08-15) Context and assumptions: - You have panel data at the region-week level ...
Derive and compare core ML and RL methods
ML Fundamentals Technical Screen — Multi‑part Question Context: You are given a set of core machine learning topics to address rigorously. For each pa...
Evaluate emoji reactions launch
A messaging app plans to introduce an emoji reaction feature: users can long-press a message for 5 seconds and attach an emoji instead of sending a te...
Determine if users need a new feature
Scenario You are a Data Scientist supporting a consumer product team considering launching a new feature (e.g., a new group-calling/chat feature). You...
Design a time-series home-buy decision classifier
Take‑Home: Classifying Buy‑Now vs Wait Decisions in Housing Time Series Context You are given a monthly panel of regional housing and macro time serie...
Analyze spend and creation-source shifts
You are working with ads data. Assume the following tables, with all timestamps interpreted in UTC. - advertisers(advertiser_id BIGINT, advertiser_cat...
Frequent Traveler Case
You are a data scientist at a professional networking platform. Using coarse location signals such as city-level login location, IP geolocation, GPS, ...
One of the most comprehensive LinkedIn DS Product Cases!
You are a Data Scientist working on LinkedIn's profile experience. Define, diagnose, and improve profile completion. Answer these questions: 1. How wo...
Use Bayes for factory identification
Bayesian inference: Which factory given two black widgets? Setup - Two factories produce red and black widgets. - Factory A: 40% red, 60% black. -...