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.

"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."
Solve min window & animal conflicts
Question LeetCode 76. Minimum Window Substring: Given strings s and t, return the smallest substring of s that contains every character of t (includin...
Explain variance reduction in random forests
Consider a random forest (or bagged ensemble) that predicts at a fixed input \(x\) by averaging \(B\) tree predictions: \[ \hat f_B(x) = \frac{1}{B}\s...
Single Queue vs Multiple Queues — Service Design
Bank Branch Queue Design: Single Line to c Tellers vs c Independent Lines Context and assumptions for comparability: - Arrivals are approximately Pois...
Diagnose Job Application Decline: Funnel Analysis and Segmentation
Scenario LinkedIn (a recruiting / job-search platform) sees a sudden, sharp decline in its Job Application metric (completed job applications submitte...
Design O(1) insert/delete and frequency-weighted random
Problem Design a data structure that supports the following operations in average \(O(1)\) time: 1. add(x) -> bool - Inserts value x into the colle...
Explain HTTP verbs, CSS, and accessibility
Frontend Fundamentals: HTTP Methods, CSS Styling, and Accessibility Context You are preparing for a frontend engineering interview question that spans...
Explain a project and handle ambiguity
Behavioral & Leadership: End-to-End Project + Ambiguous Production Incident You are interviewing for a Software Engineer (Onsite) role. Provide a conc...
Choose better bank queue and describe distributions
You are interviewing for a data role and are asked several probability/distribution questions. 1) Bank queue choice (queueing intuition) A bank has 5 ...
Implement alert queries and spike detection
You are building an in-memory alert analytics component. Each alert has: - timestamp (integer seconds since epoch) - severity (one of a small fixed se...
[SQL] Job Ad Metrics with Applicant Filter
Job Ad Metrics Analysis Task Table Structure Table: job_activity job_id INT candidate_id INT activity_type VARCHAR -- can be 'view' or 'apply' Requi...
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 ...
Reverse a linked list
Question LeetCode 206. Reverse Linked List — Given the head of a singly linked list, reverse the list and return the reversed list. https://leetcode.c...
Implement fast sampling for weighted k-sided die
You must sample from a categorical distribution over k outcomes with probabilities p1..pk (sum to 1) without using built-in categorical samplers. You ...
Compute total covered interval length
Given a list of integer intervals [l, r) (half-open), compute the total length covered by at least one interval. Intervals may overlap or be nested. R...
Design Experiments for Email Campaign & Messaging Update
Experiment Design for Concurrent Email Campaign and New Messaging Feature Context: Marketing will run an email campaign at the same time Product ships...
Measure Success of New B2B Product
Scenario A new LinkedIn B2B product has launched. Leadership wants to understand whether it adds value and what its growth potential is. Assume a typi...
Find dictionary words matching a phone digit string
You are given: - A digit string digits consisting of characters '2'–'9'. - A list of lowercase words words (dictionary). Use the classic phone keypad ...
Implement map and render to DOM
Build a Vanilla JS map-like Utility and DOM Renderer Context You are working in a basic browser environment with no frameworks or libraries. Implement...
Differentiate Java final, finalize, finally
Differentiate Java's final, finalize, and finally. Define what final means for variables, methods, and classes and give examples; explain what finaliz...
Design distributed parallel job processing
Design a Distributed System for Parallel Job Execution Context You are asked to design a highly available, horizontally scalable service that executes...