Data Scientist Interview Questions
Practice 3,071 real Data Scientist interview questions for 2026. Covers companies like Amazon, Google, Capital One, and TikTok. Real questions from actual interviews with detailed solutions. These Data Scientist interview questions are drawn from product, analytics, and modeling roles and designed for interview preparation that targets SQL fluency, statistical thinking, and applied machine learning across entry to senior levels. Expect interviews that evaluate product-metric intuition, experiment design and causal inference, and practical ML system tradeoffs. Amazon and Google lean hard on experimentation, metrics diagnosis, and scalable modeling; Capital One emphasizes statistical rigor, risk-modeling, and feature engineering; TikTok focuses on ranking/recommendation thinking, time-series/product analytics, and heavy SQL. Typical preparation includes timed SQL and Python practice, refreshing hypothesis testing and A/B design, and building short case-style stories that tie analysis to product impact.
"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."
List Top Customers and Monthly Order Counts in SQL
Orders | order_id | customer_id | order_date | amount | |----------|-------------|------------|--------| | 1 | 101 | 2023-01-05 | 120.5...
Explore Titanic Dataset: Survival Rates, Age, and Correlations
titanic_passengers +--------------+--------+--------+-----+----------+ | passenger_id | pclass | sex | age | survived | +--------------+--------+--...
Calculate Defect Rate and Identify Top Lanes for Carriers
shipment +-------------+----------+-----------+---------+---------+-------------+-----------+ | shipment_id | order_id | ship_date | carrier | origin ...
Analyze Recent User Activity from Video Call Logs
video_calls caller | recipient | ds | call_id | duration 123 | 456 | 2019-01-01 | 4325 | 864.4 032 | 789 | 2019-01-01 | 9395 | 263.7 456 | 032 | 2019-...
Explain Treatment Results and Recommend Launch Criteria for Experiments
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Explain Propensity Score Matching and Assess Covariate Balance
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Calculate Response Rate and Compare New vs. Existing User Scores
survey_events +---------+------------+-----------+--------------+---------------------+ | user_id | is_new_user| responded | survey_score | event_time...
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You are playing a one-player game with two opaque boxes, both of which start empty. The game lasts exactly 100 turns, and on every turn you must choos...
Optimal Stopping for Die Rolls That Bust on Perfect Squares
You repeatedly roll a fair six-sided die and keep a running cumulative sum $S$ of all the values rolled so far (starting from $S = 0$ before the first...
Find available reservation time slots
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Design Excel visuals for risk results
Design Excel visuals for risk results Excel Dashboard Design: Communicating EL, RWA, and Concentration Risk Context You are preparing an Excel dashboa...
Stone Pile Doubling Game: Can One Pile Be Emptied?
You are given two piles of stones containing a and b stones respectively (both piles start non-empty). You repeatedly apply the following move: - Let ...
Calculate Cumulative Sum for Each Integer in Table
numbers +-----+ | num | +-----+ | 1 | | 2 | | 13 | | 14 | | 15 | +-----+ Scenario You have a table containing one integer per row; for each row...
Analyze User Purchase Behavior in Online Marketplace Data
user_events +----------+------------+---------------------+-------------+ | user_id | event_type | event_timestamp | product_id | +----------+--...
Calculate Payback Period for Solar and Corn Projects
Calculate Payback Period for Solar and Corn Projects Energy One must choose between two renewable projects using a simple payback metric: years until ...
Calculate Weekly Revenue and Order Count for Standard Deliveries
instacart_orders +----------+---------+---------+------------+---------+--------------+ | order_id | user_id | revenue | created_at | geo | delive...
Analyze Global Engagement and Impressions with SQL Queries
impressions +---------+---------+----------+----------------+ | user_id | country | category | impression_cnt | +---------+---------+----------+------...
Analyze Recent Orders Dataset with Python/pandas
orders | order_id | user_id | price | created_at | |----------|---------|-------|------------| | 1 | 101 | 20.5 | 2024-01-01 | | 2 ...
Analyze and Clean European Ecommerce Sales Data
sales +----------+-------------+------------+---------+---------+----------------+ | order_id | customer_id | order_date | country | revenue | product...
Consolidate and Rank Global Salaries in USD
employees_us +---------+----------+--------+---------+ | emp_id | name | salary | country | +---------+----------+--------+---------+ | 1 |...