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."
Estimate billboard reach and impressions
Digital Billboard: Weekly Reach, Impressions, and Store-Visit Attribution Context You are estimating the performance of a single digital billboard bes...
Compare CNN/RNN/LSTM and implement K-means
Deep Learning Concepts and K-means Implementation (Onsite ML Interview) This is a two-part onsite round for a Data Scientist role: a conceptual deep-l...
Write complex SQL on DoorDash data
You are given the following BigQuery-style schema and tiny samples (assume timestamps are UTC; assume promotions.discount_amount is the applied discou...
Reverse linked lists, including k-group
Singly Linked List Reversal — Variants and Edge Cases You are given a standard singly linked list with nodes of the form: - Node fields: value, next -...
Explain NVIDIA fit and role value
Behavioral Prompt: Why NVIDIA and Why This Data Scientist Role? You are interviewing for a Data Scientist position. In a concise, 1–2 minute answer, a...
Solve date, shopping, and circle problems
Take‑Home: Three Independent Tasks (Data/Algorithms) Implement three independent functions that will be unit‑tested separately. Provide clear error ha...
Design and critique an abuse-detection ML system
ML System Design: Abusive Content Detection and Triage (Trust & Safety) Context: You are designing an ML system to identify and triage abusive content...
Lead a product deep dive with quantified impact
Behavioral Product Leadership Prompt (Data Scientist) You are interviewing for a Data Scientist role with a strong focus on product analytics, experim...
Drive product decisions with causal product sense
Experimenting on a New Paywall with Likely Spillovers Context You are designing an experiment to evaluate a new paywall on a social/content app where ...
Count Interior Islands After Flooding
You are given an m x n binary grid representing land and water. - 1 = land - 0 = water An island is a maximal group of land cells connected 4-directio...
Implement Buffer Parsers and Generic Map Class
In C++, complete the following two independent implementation tasks. 1. Sequential buffer reader You are given a raw byte buffer and a current poin...
Find missing numbers in sequences
You are given several number sequences (integers and/or rational numbers). Each sequence contains exactly one missing term written as ?. For each sequ...
Should You Cancel or Sell Analyst?
You are the CEO of a media company. One of your current TV shows is Analyst. The show has about 2 years of remaining commercial life. You are deciding...
Quantify and Model Flight Delays Using Statistical Tests
Flight Delays: Quantification, Modeling, and Testing a Mitigation Strategy Scenario You are a data scientist investigating flight delays using histori...
Investigate Super Bowl Ad Impact on User Sign-Ups and Revenue
Scenario A crypto exchange airs a Super Bowl commercial featuring a QR code that awards a $15 coupon to anyone who scans it and completes sign-up. Sho...
Investigate Causes and Effects of Dynamic Pricing on ETAs
Scenario Lyft notices that ride wait times (ETA) have increased 20% month-over-month. The team suspects that static pricing may be the culprit and is ...
Compute sample size and Bayes posterior
You are implementing two small statistical utilities. Part A — Power / sample size (two-sample z-test) - Input: - x: a 1D numeric array of historica...
Design a short-video recommendation system
Design a recommendation system for a short-video feed product. Your answer should cover the full pipeline: 1. Objective and labels: Define what the sy...
How would you lead a team to improve quality?
Behavioral / Leadership — Leading a Team to Improve Quality You are acting as a Tech Lead (TL) for a small cross-functional team (e.g., 4–8 engineers ...
Do US members upload more videos than non-US?
You suspect video posting adoption differs between US and international members. Tables members - memberid INT (PK) - country VARCHAR (e.g., 'usa', '...