Software Engineer interview questions at Google

646 verified questions reported by Software Engineer candidates interviewing at Google. Each one is archetype-tagged so you can see the pattern, slot the right STAR story, and practice out loud against an AI interviewer that pushes back the way a real one would.

Top 25 verified questions

Sorted by quality score (specificity, clarity, practice-worthiness) with a tie-break on most recently observed.

1. 1
   Walk me through how you would architect a recommendation engine capable of serving personalized suggestions for a platform with 50 million active users.

   system design·onsite
2. 2
   You have pre-rendered static tiles cached on CDN. Traffic conditions change every few minutes. Re-rendering and re-caching billions of tiles every few minutes is too slow and expensive. How do you overlay dynamic traffic data on static tiles?

   system design·system design·technical
3. 3
   Phone GPS has 5 to 15 meter accuracy. A stationary phone looks identical to a traffic jam. A phone moving slowly through a school zone looks like congestion. With billions of noisy GPS points how do you ensure traffic computation reflects actual road conditions?

   system design·system design·technical
4. 4
   Walk me through the real-time synchronization process when a user types a character in a collaborative document editing system.

   system design·onsite
5. 5
   How would you architect a real-time fraud detection system for processing 10,000 financial transactions per second?

   system design·onsite
6. 6
   Walk me through your systematic approach to troubleshooting a production service outage when the root cause is initially unclear.

   situational·onsite
7. 7
   Design an algorithm to maximize the total value of items you can pack into a container, where each item type can be selected multiple times.

   technical·technical
8. 8
   Dijkstra exploring all roads equally for a Mumbai to Delhi query wastes enormous computation on tiny side streets that could never be part of the optimal route. How do you make routing dramatically faster?

   system design·system design·technical
9. 9
   How would you design a concurrent health check system that can efficiently validate the status of 10,000 servers using Goroutines or Asyncio?

   technical·onsite
10. 10
    How would you architect a machine learning system to detect and filter spam emails in a high-volume enterprise email environment?

    system design·onsite
11. 11
    Describe the Linux kernel and system-level techniques you would use to diagnose whether a process is genuinely hung or unresponsive.

    technical·onsite
12. 12
    User searches Italian restaurants near me. Results must consider both text relevance and geographic proximity simultaneously. A Starbucks 200 meters away is more relevant than a better rated one 20km away. How do you design location search?

    system design·system design·technical
13. 13
    500 million Android phones with Google Maps open send GPS location every few seconds. Google must process this to detect traffic patterns in near real time. How do you design the pipeline that converts billions of location updates into real time traffic conditions?

    system design·system design·technical
14. 14
    Walk me through your experience with Redux and how you've applied it in managing complex application state.

    technical·technical
15. 15
    Describe a challenging leadership decision you've made. What was the strategic reasoning, and what were the key outcomes and lessons learned?

    behavioral·behavioral
16. 16
    How would you implement an in-place reversal of a singly linked list with O(n) time complexity and O(1) space complexity?

    technical·technical
17. 17
    Walk me through the most technically challenging project you've delivered, and explain the specific obstacles you overcame.

    behavioral·onsite
18. 18
    Walk me through how you would architect a real-time collaborative text editor that supports multiple concurrent users.

    system design·onsite
19. 19
    Design a concurrent API client that can fetch from 100 endpoints while maintaining a 10 request/second rate limit and implementing strict timeout handling.

    technical·phone screen
20. 20
    Describe the peak request volume and user concurrency your most recent system was designed to support.

    system design·onsite
21. 21
    Walk me through how you would diagnose a sudden p99 latency spike in a photo upload service, given no apparent application-level errors.

    system design·technical
22. 22
    Walk me through designing a distributed storage service that ensures 99.99% availability using 500 HDDs with a 2% annual failure rate.

    system design·onsite
23. 23
    How would you select the appropriate unit of randomization when designing an A/B test to ensure statistically valid results?

    technical·technical
24. 24
    How would you architect a real-time fraud detection system capable of processing 10,000 transactions per second with sub-50ms latency?

    system design·onsite
25. 25
    Walk me through a complex technical project you've led, highlighting how you coordinated team efforts and managed technical challenges.

    behavioral·phone screen

Common questions