LinkedIn Interview Questions
Practice 142 real LinkedIn interview questions for 2026. Covers all top categories — Coding & Algorithms, System Design, Analytics & Experimentation, Data Manipulation (SQL/Python), and Behavioral & Leadership — across Software Engineer, Data Scientist, Machine Learning Engineer, and Data Engineer roles. Real questions from actual interviews with detailed solutions; this collection is designed for focused interview preparation that prioritizes coding and scale-first problem solving alongside rigorous metrics thinking. Expect LinkedIn interviews to evaluate production-ready tradeoffs, clear metricization of ranking and relevance, and the ability to diagnose live-traffic regressions. For Software Engineer candidates, recurring themes include constant-time randomized data structures and frequency-weighted sampling, Top-K ranking service design and distributed-scaling considerations, plus classic array/string and stack-with-max algorithmic problems. Data Scientists should be ready for model fundamentals and optimization (logistic regression, backprop, Adam), causal and experimentation diagnostics for feed/homepage drops, and sampling/variance concerns in ranking metrics. Machine Learning Engineers will see recommendation and skills-inference system design, clustering convergence and probabilistic sampling questions, and production alerting/spike-detection. Data Engineers encounter efficient data-structure implementations tied to measurable production impact.
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"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."
Decide best email variant using stratified A/B analysis
Stratified A/B Test Across Two Strata (Week/Location) You ran an email A/B test across two strata defined by week/location. Each user receives at most...
Explain database transactions and ACID
Database Transactions and ACID under Concurrency Prompt You are working with a relational database that supports transactions and multiple isolation l...
How to analyze Simpson's paradox
A marketing team wants to evaluate a new email campaign. Two email versions, A and B, were tested over two weeks in two cities: San Francisco and New ...
Design an in-memory key-value store using maps
Design a low-level key-value store library (like an embedded storage engine) under an interview constraint: you may use only map/dictionary-like data ...
Design scalable job scheduler and query dashboard
Design a scalable, fault-tolerant job scheduling system. The system should allow clients to schedule background jobs (for example, sending emails or r...
Design a Top-K search words service
Scenario Design a service that tracks user search queries and returns the Top-K most searched words/queries. Requirements Functional - API to record a...
Measure Relevant Feed Success
LinkedIn changes the Home Feed default experience from showing all content to showing only content predicted to be relevant to each viewer. How would ...
Train with imbalanced sampled data
You are training a binary classifier on a very large dataset where the positive class is rare. Because the full dataset is too large to train on direc...
Write SQL for rankings, state, and aggregations
You are given several independent datasets. For each dataset, write the required SQL query (ANSI SQL is fine). Assume dates are in UTC and DATE column...
Group words that map to same phone digits
Problem On a classic phone keypad (T9), letters map to digits: - 2: ABC, 3: DEF, 4: GHI, 5: JKL, - 6: MNO, 7: PQRS, 8: TUV, 9: WXYZ Given a list of lo...
Solve Cache, Window, and Heap Problems
You may be asked to solve multiple algorithmic problems in coding rounds: 1. Frequency-based cache: Implement a cache with get(key) and put(key, value...
Design a company-wide monitoring system
You are asked to design a monitoring system used company-wide. Goals - Collect and query telemetry for many services/hosts - Support alerting and dash...
Explain your most impactful project clearly
Technical Communication / Behavioral Describe the project you worked on that had the largest measurable impact. The interviewer asks you to: 1. Whiteb...
Implement stream random sampling in Python
You are given an unbounded stream of items that cannot be stored entirely in memory. Write Python code to maintain a uniform random sample from the st...
Sample index from probability distribution
You are given a discrete probability distribution for an \(M\)-sided die as an array p[0..M-1], where each p[i] is non-negative. Design a function sam...
Explain activations, losses, and Adam
Answer the following ML fundamentals questions: 1) Neural network building blocks - What is a "layer" in a neural network, and what does it compute? -...
Process Mutable Matrix Sum Queries
You are given a 2D integer matrix and a list of queries. There are two query types: - set r c v: update the value at row r and column c to v - get r1 ...
Design a metrics platform without alerting
Design a metrics platform (like a simplified Prometheus/Datadog metrics product) that supports collecting, storing, querying, and visualizing metrics....
Find shortest word transformation with caching
You are given a start word and an end word of equal length, and a dictionary of valid words. In one move you may change exactly one letter to form a n...
Improve Profile Completion Rate
Increasing LinkedIn Profile Completion — Analytics & Experimentation (Onsite) Context Profile completeness affects members' visibility in search, qual...