Google Interview Questions

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.

514 Questions 1 Company08.01.2026
Showing 20 results
Role
Google logo
Google
Hard
Machine Learning Engineer

Explain transformer architecture and variants

Technical Screen: Explain the Transformer Architecture Scope Provide a structured deep-dive into Transformers. Your explanation should cover theory, s...

Machine Learning
25
0
173 people solved
Sep 6, 2025
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Google
Medium
Software Engineer Locked

Implement text wrapping, waitlist, and intervals

This question evaluates skills in string parsing and word-wrapping logic, data-structure design for FIFO queue management and deletions, and interval ...

Coding & Algorithms
19
0
152 people solved
Feb 12, 2026
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Google
Easy
Software Engineer Locked

Compute decayed power levels in a graph

This question evaluates knowledge of graph algorithms and distance-based propagation, testing concepts such as shortest-path distance computation, mul...

Coding & Algorithms
18
0
151 people solved
Feb 12, 2026
Google logo
Google
Medium
Software Engineer

How would you answer these behavioral prompts?

You are in a behavioral interview. Prepare structured answers (with concrete examples) for the following prompts. Expect follow-ups such as: Why was y...

Behavioral & Leadership
6
0
62 people solved
Jan 6, 2026
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Google
Medium
Data Scientist

Design pricing and multivariate button experiments

You join a B2B SaaS firm with three public tiers (Basic $25/month, Pro $50/month, Enterprise = sales-quoted). The PM asks for a 2‑week A/B test to rai...

Analytics & Experimentation
10
0
120 people solved
Oct 13, 2025
Google logo
Google
Medium
Data Scientist

Narrow a confidence interval for a mean

You have a simple random sample with n = 100 and sample mean 100. The current 95% CI for the population mean is 100 ± 10, which a PM says is too wide....

Statistics & Math
11
0
139 people solved
Oct 13, 2025
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Google
Medium
Data Scientist Locked

Estimate 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
72 people solved
Oct 13, 2025
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Google
Medium
Data Scientist

Design an A/B test with guardrails and SRM checks

You are launching a new personalized ranking on the product listing page. Define: (a) the primary success metric and its exact formula (include numera...

Analytics & Experimentation
9
0
153 people solved
Oct 13, 2025
Google logo
Google
Hard
Data Scientist

Experimentally evaluate jogging-route recommendations

Design an Evaluation for Jogging Route Recommendations in Maps Objective Design an A/B test and evaluation framework for recommending optimal jogging ...

Analytics & Experimentation
11
0
126 people solved
Oct 13, 2025
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Google
Medium
Data Scientist

Diagnose a metric drop in search time

Over the last 3 calendar months, the metric 'searching time per user per session' dropped by 35%. A teammate proposes modeling two distributions: T1 =...

Analytics & Experimentation
6
1
82 people solved
Oct 13, 2025
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Google
Medium
Software Engineer Locked

Solve Shortest Paths and Rental Allocation

This question evaluates understanding of shortest-path algorithms and reachability in weighted graphs (including directed vs. undirected handling and ...

Coding & Algorithms
6
0
45 people solved
Apr 12, 2026
Google logo
Google
Medium
Software Engineer

Find the Largest Monotone Increasing Number

Find the Largest Monotone Increasing Number Problem Given a non-negative integer n, return the largest integer less than or equal to n whose decimal d...

Coding & Algorithms
6
1
18 people solved
Jul 4, 2026
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Google
Medium
Software Engineer

Check Whether Digits Are Monotone Increasing

Check Whether Digits Are Monotone Increasing Problem A non-negative integer has monotone increasing digits when every adjacent pair of digits is non-d...

Coding & Algorithms
4
0
18 people solved
Jul 4, 2026
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Google
Medium
Machine Learning Engineer

Describe leadership under changing priorities

Prepare structured answers for these behavioral questions: - Tell me about a time you went above and beyond expectations. - Tell me about a time you f...

Behavioral & Leadership
6
0
56 people solved
Jan 19, 2026
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Google
Hard
Software EngineerNew Grad Locked

Compute Turnstile Crossing Times

This question evaluates proficiency in queue simulation, event-driven scheduling, and handling priority and tie-breaking rules while achieving linear ...

Coding & Algorithms
5
1
50 people solved
May 4, 2026
Google logo
Google
Medium
Machine Learning Engineer

Implement a robust Python generator

Given a list of integers, write a Python generator that yields the integers from the list while handling edge cases such as None values, empty input, ...

Data Manipulation (SQL/Python)
9
0
96 people solved
Sep 6, 2025
Google logo
Google
Hard
Software Engineer

Design key management service

Design a Key Management Service (KMS) You are asked to design a production-grade, multi-tenant Key Management Service. A client provides a key identif...

System Design
8
0
137 people solved
Sep 6, 2025
Google logo
Google
Hard
Software Engineer

Design distributed log storage service

Design a Distributed Append-Only Log Storage System You are asked to design the storage layer of a distributed, partitioned, replicated append-only lo...

System Design
12
0
92 people solved
Sep 6, 2025
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Google
Medium
Machine Learning EngineerSenior+ Locked

Design ML system for self-driving perception

This question evaluates understanding of end-to-end ML system design for on-vehicle obstacle detection and collision avoidance, encompassing sensor fu...

ML System Design
14
0
117 people solved
Dec 8, 2025
Google logo
Google
Medium
Software Engineer

Describe a major challenge you faced

In a behavioral interview for a software engineering or technical role, you are asked: > Describe the most significant challenge you have faced in an ...

Behavioral & Leadership
5
0
62 people solved
Dec 8, 2025

Frequently Asked Questions

How hard are Google interview questions and how does difficulty vary by level?
Google interview questions are challenging but predictable: they range from medium algorithmic problems for new grads to hard, system- and architecture-focused problems at senior levels. L3/new-grad interviews emphasize correct, clean code with solid complexity and edge-case handling; expect two to three coding rounds plus a Googleyness/leadership conversation. L4 requires optimal solutions, clearer trade-off communication, and sometimes a system-design or domain round. L5 raises the bar on system design, scalability, ownership, and leadership impact. Non-SWE roles shift emphasis toward statistics, experiment design, or model-building depending on the job.
What does the Google interview process look like and where do these 514 questions appear?
The typical loop starts with a recruiter screen, one or more phone or virtual coding screens, then a virtual or in-person onsite loop of 3–5 forty-five minute interviews: mostly coding, plus a Googleyness/leadership behavioral round and usually one domain or system-design session for mid and senior roles. The 514-question corpus covers those stages: phone-screen style coding, onsite deep-coding, system-design prompts, analytics/experiment questions for data roles, ML implementation prompts, and product-spec behavioral cases. Hiring committee review, level calibration, and team match happen after the loop and extend timelines by several weeks.
How should I schedule my preparation and how much time do I need to prepare effectively?
Plan prep based on level and role: new grads should spend 4–6 weeks focused on core data structures, algorithm patterns, and 4–6 polished STAR stories. Mid-level L4 candidates should budget 6–10 weeks, adding system design and production-readiness topics plus mock interviews. L5 and above need 8–12+ weeks emphasizing architecture, trade-offs, and leadership narratives. Break weeks into coding practice, timed mocks, system-design sprints, and role-specific work (experiments for DS, model lifecycle for MLE). Run at least 6–10 realistic mock interviews and iterate on communication and edge-case testing.
What specific subtopics and recurring themes should I expect by role at Google?
For Software Engineer interviews expect spatial and streaming geometry problems (counting or removing points within distance), concurrency and async primitives, deterministic task ordering and schedulers, calendar/free-slot algorithms, boolean-expression fixes, array/subarray patterns, and small-system OOD prompts like dorm room assignment. Data Scientist questions concentrate on causal and experiment design, funnel and product-metric computation, unbiased upgrade experiments, bootstrap and percentile estimation from buckets, sampling algorithms, and applied modeling like shot-conversion. Machine Learning Engineer rounds emphasize transformer/LLM building blocks and trade-offs, recommendation and ranking cold-start strategies, weighted sampling, and implementation details.
Any standout tips and common pitfalls, including level-specific advice (L3, L4, L5) and intern/new-grad notes?
Start by matching preparation to level: L3/new-grad must deliver correct, well-tested code and clear complexity; L4 must reach optimal solutions, explain trade-offs, and show production thinking; L5 must demonstrate architecture, scaling trade-offs, and cross-team impact. For interns/new-grads expect a phone coding screen followed by a virtual onsite; practice timed screens and basic system thinking. Across levels, talk through examples, define constraints, test edge cases, and avoid premature optimization or vague assumptions. Prepare 4–6 STAR stories for Googleyness, and don’t overlook clear, testable code and thought-out system trade-offs.

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