Google Coding & Algorithms Interview Questions
Practice 514 real Google interview questions for 2026. Covers Coding & Algorithms, Behavioral & Leadership, Analytics & Experimentation, Machine Learning, and System Design across Software Engineer, Data Scientist, Machine Learning Engineer, Product Manager, and Data Engineer roles — real questions from actual interviews with detailed solutions to accelerate interview preparation. This collection highlights the coding-first bar Google uses: expect heavy algorithmic work, role-related data and ML problems, a Googleyness/leadership round, and level-specific differences in what’s decisive. What’s distinctive: for Software Engineers you’ll see spatial and streaming algorithms, concurrency and async primitives, LLM-foundations and GPU-job scheduling, plus object-design problems like room assignment; Data Scientists are weighted toward causal experiments, funnel and product-metric diagnostics, bootstrap inference, and percentile/sampling algorithms; ML Engineers focus on transformer blocks, recommendation design and ranking cold-starts; PMs get Maps/Android and product-ideation tradeoffs plus throughput and revenue sizing. New-grad and intern tracks emphasize phone screens and virtual onsites; Google L4 typically keeps the loop coding-heavy while Google L5 expects stronger system-design and cross-team leadership signals. Use focused practice, mock interviews, and level-specific stories to prepare.

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"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."

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"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."
Design a waitlist system with top/bottom K
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Answer leadership and quality tradeoff questions
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Clarify ambiguous requirements under pressure
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Design long-tail search evaluation under label budget
Estimating ΔNDCG@10 With Limited Labels Under a Heavy-Tailed Query Mix You serve ~100M queries/day. Query frequencies follow a Pareto distribution wit...
Prove 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...
Compute p-values, probabilities, and regularization choices
Answer all parts. A) Hand‑compute a two‑sided p‑value comparing two means using Welch’s t‑test. Sample A: n1=20, mean1=5.2, sd1=1.1. Sample B: n2=24, ...
Design nearest-available-taxi lookup with updates
This question evaluates the ability to design scalable, low-latency geospatial lookup services under high update and query rates, assessing skills in ...
Convert Valid Snake Case to Lower Camel Case
Convert Valid Snake Case to Lower Camel Case Given a valid snake-case identifier, convert it to lower camel case. The input consists of one or more lo...
Explain ML model fundamentals
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Generate values by weighted probabilities
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