Machine Learning Interview Questions
Practice 639 real Machine Learning interview questions for 2026 — Machine Learning interview questions drawn from Amazon, Meta, Google, TikTok, and Capital One, with real questions from actual interviews and detailed solutions. This collection is built for interview preparation focused on production-ready ML: expect questions that test modeling and mathematics, coding in Python, ML system design, MLOps and deployment, and modern GenAI topics such as transformer fundamentals, embeddings, and retrieval-augmented generation. Companies emphasize reliability, data quality, and end-to-end ownership as much as algorithmic chops. What’s distinctive: interviews now blend theory, coding, and system thinking — you’ll be evaluated on algorithmic intuition, experiment design and metrics, feature and data engineering, model monitoring and drift detection, and cost/reliability tradeoffs for serving models at scale. To prepare, strengthen fundamentals (linear models, trees, probabilistic reasoning), implement end-to-end projects, rehearse ML system-design case studies, and run mock interviews that combine coding, math, and production scenarios.

"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."
Explain Overfitting and Underfitting in Machine Learning
ML Fundamentals and Computer Vision: Core Concepts Instructions You are interviewing for a data science role focused on classical ML and computer visi...
Address Missing Income Bracket in California Housing Data
ML Case: Missing Lowest-Income Bracket in California Housing Data Context You're building a supervised model (regression) to predict California housin...
Identify Algorithms for Detecting Malicious Duplicated Content
Detecting Malicious Duplicated Text (DOT) Scenario You are selecting technical approaches for DOT, a bot‑detection tool aimed at finding malicious dup...
Evaluate Ensemble Models for Bias-Variance, Speed, and Interpretability
Large-Scale Recommendation System: Ensembles, Overfitting, Metrics, Architectures, and Optimization Context You are designing a large-scale recommenda...
Explain Deep Learning to a 5-Year-Old Child
Microsoft Phone-Screen: Machine Learning Fundamentals You are interviewing for a machine learning/data science role and should provide concise, struct...
Evaluate Product-Ranking Algorithm with Precision and Recall Metrics
Scenario Instagram Shopping wants to improve its product‑ranking algorithm for the shopping feed. The goal is to select and order products for each us...
Handle missing and unavailable predictive features
Scenario You are building a model to predict whether a user will successfully file taxes (binary label success) for a TurboTax-like product. One of th...
Handle missing values for LGD modeling
Handling Missing Values for LGD Modeling Context You are building a Loss Given Default (LGD) model using account- and borrower-level features captured...
Design bot detection and evaluate trade-offs
Bot-Detection System Design for Comment Activity Context You are designing and evaluating a machine learning system to detect automated (bot) comment ...
Build and evaluate illegal-video classifier
End-to-End ML System Design: Flag Illegal YouTube Videos You are tasked with designing a production ML system to detect and triage potentially illegal...
Explain random forests, bagging, and evaluation
Random Forests, Bagging vs Boosting, and Practical Model Validation You are building a supervised learning model on tabular data. Explain and compare ...
Decide standardization, sparse numerics, correlated features
You are given a tabular dataset for supervised learning with features: F1 (counts, mostly small integers with many zeros), F2 (monetary amounts in dol...
Design anomaly detection and handle imbalanced logistic regression
You receive a time‑stamped transactions dataset: columns [event_time (UTC), customer_id, merchant_id, amount, country, device_type, features...], labe...
Tune metrics for imbalanced classification
Fraud Detection With Rare Positives (0.5%) and Messy Data You are designing a supervised transaction-level fraud detector. Positives (fraud) are rare ...
Minimize max L1 radius with k centers in 1D
You are given an array A of n integers (values may be negative and may repeat) and an integer k (1 ≤ k ≤ n). Place k cluster centers anywhere on the r...
Build predictive model for feature rollout targeting
Before global launch, you want to predict which users or products would benefit most from the 'More like this' button so you can stage rollout. Design...
Evaluate fraud classifier with cost-sensitive metrics
Binary Fraud Classifier: Metrics, Thresholding, Calibration, and Online Evaluation You inherit a binary fraud classifier used to decide whether to blo...
Design a hybrid marketplace fraud system
Design a Fraud Detection System for a Marketplace and Profile Credentials Context You are a data scientist at a two‑sided marketplace where users can ...
Optimize IG Shopping ranking with multiple objectives
Instagram Shopping: Multi-Objective Ranking With Fairness, Fraud Robustness, and On-Device Constraints You are designing the Instagram Shopping home f...
Design a restaurant recommender under cold start
Design a Multi-Objective Restaurant Ranking System You own the restaurant recommendation surface for a city app. The goal is to rank nearby restaurant...