Interview Questions
Practice the exact questions companies are asking right now.
Questions
10.0k
Companies
520
Updated
08.21.2026
10.0k Questions 520 Companies08.21.2026
PLTCHK
"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"
_The_TaNk_
"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"
ChrisSenior SWE, LinkedIn
"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."
sleepy33
"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."
JakeSenior ML Engineer, Lyft
"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."
nuggetlord
"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."
CarlosFull Stack, Shopify
"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."
boba.tea.vibes
"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."
AndySWE-II, Google
"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."
couchpotato99
"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."
ShrutiData Engineer, Salesforce
"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."
midnightramen
"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."
BiancaFrontend Eng, Figma
"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."
tambrahm007
"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
toa
"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."
Showing 20 results
Role
Medium
Data ScientistRemove shortest subarray to sort array
Given an integer array nums (length up to 2×10^5), return the shortest subarray [L,R] you can remove so that the remaining elements form a non‑decreas...
Coding & Algorithms
5
0
69 people solved
Oct 13, 2025
Hard
Data ScientistMeasure impact of bot mitigation via experiment
Experiment Design: Measuring the Impact of a Bot‑Mitigation System Context You are evaluating a production change to a large social platform that hide...
Analytics & Experimentation
9
0
102 people solved
Oct 13, 2025
Easy
Data ScientistDifferentiate fixed and variable costs with examples
Unit Economics: Fixed vs. Variable Costs in a Subscription Streaming Business Task - Define fixed cost vs. variable cost for a subscription streaming ...
Statistics & Math
6
0
58 people solved
Oct 13, 2025
Medium
Data ScientistDesign late-tolerant streaming window aggregator
You receive an unbounded stream of events: (event_time, user_id, category). Events may arrive up to 48 hours late and are not ordered by time. Design ...
Coding & Algorithms
8
0
81 people solved
Oct 13, 2025
Hard
Data ScientistOptimize amusement park pricing, capacity, and testing
Context You are interviewing for a Data Scientist role focused on analytics and experimentation. An amusement park is considering launching a paid Fas...
Analytics & Experimentation
8
0
84 people solved
Oct 13, 2025
Hard
Data ScientistDefine and validate an airline profitability metric
Airline Route Profitability Metric with Quality Guardrails Context You need a single, decomposable primary metric for airline route profitability that...
Analytics & Experimentation
5
0
95 people solved
Oct 13, 2025
Medium
Data ScientistEstimate population singletons from a 10% log
A daily search log has one row per query string. You draw a 10% simple random sample of rows without replacement. Define a “unique query” (singleton) ...
Statistics & Math
25
0
170 people solved
Oct 13, 2025
Medium
Data ScientistProve OLS invariance to linear transforms
You fit Model 1: y ~ X1 + X2. You also fit Model 2 using Z = [X1 − X2, X1 + X2] = X T where T = [[1,1], [−1,1]] (2×2, invertible). a) Prove that OLS p...
Statistics & Math
12
0
110 people solved
Oct 13, 2025
Medium
Data Scientist LockedEstimate unbiased ad scores with many reviewers
This question evaluates a candidate's skills in hierarchical and mixed-effects modeling, latent-variable estimation, debiasing rater severity and scal...
Statistics & Math
4
0
76 people solved
Oct 13, 2025
Medium
Data ScientistDefine and sample a truncated normal
Define the truncated normal Z | a < Z < b for Z ~ N(0,1): write the normalized pdf and cdf. Then design efficient samplers for three cases: (i) a = 1,...
Statistics & Math
5
0
72 people solved
Oct 13, 2025
Medium
Data ScientistJustify and harden your analytics and BI stack
List your current analytics tech suite end-to-end (ingestion, storage/warehouse, transformation, orchestration, catalog/lineage, experimentation platf...
Data Manipulation (SQL/Python)
7
0
85 people solved
Oct 13, 2025
Medium
Data ScientistDesign robust experiment for ambiguous core change
You must evaluate a core product change that likely has network effects (e.g., a matchmaking tweak in a large online game with 8M DAU). Define the pri...
Analytics & Experimentation
13
0
96 people solved
Oct 13, 2025
Hard
Data ScientistPrioritize a new warehouse proposal with data
Build vs. Lease vs. Defer: New Fulfillment Center Decision Context You are evaluating whether to open a new fulfillment center (FC) to improve deliver...
Analytics & Experimentation
3
0
73 people solved
Oct 13, 2025
Easy
Data ScientistCalculate profit and break-even across pricing models
Unit Economics and Break-even Analysis for a Cloud-Storage Startup You are analyzing a cloud-storage startup that currently charges unit-based pricing...
Statistics & Math
9
0
94 people solved
Oct 13, 2025
Medium
Data ScientistSolve window-function SQL without joins
You must use only window functions (no JOINs). CTEs are allowed. Given the schemas and tiny samples below, write SQL for each sub-question and explain...
Data Manipulation (SQL/Python)
7
0
57 people solved
Oct 13, 2025
Medium
Data Scientist LockedDesign Biker metrics and A/B test plan
This question evaluates a data scientist's competency in experimental design, metric engineering, causal inference, and operational analytics, focusin...
Analytics & Experimentation
3
0
34 people solved
Oct 13, 2025
Medium
Data Scientist LockedCompute robust linear interpolation with edge cases
This question evaluates understanding of linear interpolation, representation as convex combinations, handling of degenerate input cases, bounding int...
Statistics & Math
7
0
75 people solved
Oct 13, 2025
Medium
Data ScientistDescribe cross-functional collaboration under time pressure
Tell me about a time you led a cross-functional initiative with ambiguous requirements and severe time pressure. The interviewer asked generic or shif...
Behavioral & Leadership
5
0
64 people solved
Oct 13, 2025
Hard
Data ScientistApply sequential testing without p-hacking
Sequential Monitoring With Early Stopping Context: You are planning a two‑sided hypothesis test with continuous monitoring and early stopping for effi...
Statistics & Math
8
0
106 people solved
Oct 13, 2025
Hard
Data ScientistDiagnose outliers and influence in linear regression
OLS Diagnostics: Outliers, Leverage, Influence, and Cook's Distance Context You are fitting an ordinary least squares (OLS) linear regression with an ...
Machine Learning
7
0
125 people solved
Oct 13, 2025