Machine Learning Engineer + Data Scientist + Software Engineer Interview Questions
Practice the exact questions companies are asking right now.

"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."
Build a Bayes classifier for reviewer types
This question evaluates Bayesian inference skills, including posterior updating under conditional independence, likelihood modeling for categorical ob...
Impute, join, and upsert using SQL and Python
Write both SQL and Python (pandas) to complete the following data-manipulation tasks. Assume today is 2025-09-01 for any time filters. Schema: custome...
Find premium share for break-even
This question evaluates a candidate's ability to construct and manipulate a linear financial model and perform break-even analysis using algebra, basi...
Design profitability growth plan
This question evaluates a data scientist's skills in business analytics, experimentation design, and strategic framework development for profitability...
Diagnose sales correlations without claiming causality
This question evaluates a data scientist's competency in designing correlation-focused observational analyses, including exposure-window definition, c...
Compute weekly 3-week rolling sums in SQL
Using PostgreSQL, write a single query that outputs, for each calendar week in a given range, the sum of amounts in that week and a rolling sum over t...
Measure notification impact and set guardrails
This question evaluates causal inference, experiment design, metric specification and attribution, statistical power calculation, and long-term monito...
Identify latent group-call demand from behavior
This question evaluates a data scientist's ability to design measurable product-analytics signals, infer latent user demand from event-level messaging...
Clean, split, merge, and aggregate with pandas
Given two CSVs, use pandas to clean, split strings, merge, and aggregate. drivers.csv driver_id,name,signup_city D1,Jane Doe,SF D2,Mark S,NYC D3,A...
Write SQL for fares and age-band counts
You have two tables. Schema: - drivers(driver_id VARCHAR PRIMARY KEY, name VARCHAR, date_of_birth DATE) - trips(trip_id VARCHAR PRIMARY KEY, driver_id...
Check anagrams under real-world constraints
Given two strings s and t, determine whether they contain exactly the same multiset of characters (e.g., 'abc' and 'cab' → true; 'aab' and 'ab' → fals...
Design a hybrid marketplace fraud system
This question evaluates competency in designing hybrid fraud detection systems, covering feature engineering across text, image, graph and telemetry s...
Write SQL for last-7-day metrics without windows
Assume today is 2025-09-01. Use ANSI SQL only and do not use window functions. You may use subqueries, GROUP BY, HAVING, and JOINs. Schema and small s...
Design fraud detection across channels with unknowns
This question evaluates a data scientist's competence in designing and operationalizing multi-channel fraud detection systems, covering cost-sensitive...
Write SQL to flag Venmo ATO
SQL case: You are a Decision Scientist on Venmo’s Fraud (ATO) team. Using the schema and sample data below, write a single Standard SQL query that ret...
Write SQL for social feed metrics and ties
You are given the following schema (PostgreSQL) and sample rows. Assume UTC timestamps and that friendships are static over the sample window. users(u...
Implement scalable prime generator
Write a function first_n_primes(n) that returns the first n prime numbers in ascending order. Constraints: - 1 ≤ n ≤ 100,000. - Aim for O(n log log n)...
Implement deduped CTR/RPM aggregator over event stream
Implement a Python function to compute per-day, per-campaign CTR and RPM from an event stream with possible out-of-order and duplicate click events. I...
Implement streaming CTR with deduplication
Implement a Python function to compute streaming, per-campaign CTR over a sliding 24-hour window with click de-duplication and late-arriving events. R...
Calculate Year-1 profit margin
This question evaluates a candidate's ability to perform applied financial math, including profit margin calculation, classification of costs into fix...