Most Important Google Interview Questions With Answers (2025)

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Google LLC is considered the 'most powerful company globally' and one of the most valuable brands. It is an American multinational technology company with a prime focus on AI, search engine technology, cloud management, computer software, online advertising, digital marketing platforms, consumer electronics, e-commerce, and quantum computing.

Google is the dream company of almost every IT professional. However, getting into this mega-firm is not a cakewalk. The company receives about three million job applications per year from across the world and they recruit only 0.2% of these. Also, the interviews taken by Google are considered the toughest ones. But good preparation can actually make your dream come true. 

Want to excel in the Google interview? In this article, we will discuss the important Google interview questions that you could be asked. We will cover the technical Google interview questions as well as the HR round questions so that you have a good idea of the important topics for the Google interview. 

Overview of Google Recruitment Process

Before we dig into the Google interview questions, let's give you a quick overview of the Google recruitment process. 

The Google recruitment process consists of five main rounds. Here are the details:

1. Resume Screening: This is the first and foremost step in the process. A good resume helps to catch recruiters' attention and highlights all the qualities that make a candidate a right fit for the specified role.

What would you need to make your CV get shortlisted?

• A precise description of your skill set and display of the exact attributes that Google is looking for
• It should be short yet impactful 
• Professionally concise 

2. Phone screening: In this step, the candidate gets a call from the organization to give a brief idea about the company rules and provides the candidate with a detailed job description. The candidate may also have to face technical and behavioral interview questions. Based on the interaction, the candidate is shortlisted for the next round i.e. the onsite interview. 

3. Onsite interview: This round consists of 4-5 rounds where you will go through technical interviews. Apart from the technical knowledge, the candidate will be checked for teamwork ability, soft skills, excellent communication skills, and work culture acclimatization. 

Hiring manager review: The hiring manager takes the final call regarding the candidate. If selected, the top executives review the compensation and offer made by the hiring manager to the candidate before extending the offer letter.  

Now that you know the steps involved in the Google recruitment process, let's take you through the important Google interview questions to prep you well for your interview day. 

Google Interview Questions: Technical 

1. Count of strings that can be formed using a, b and c under given constraints

Given a length n, count the number of strings of length n that can be made using ‘a’, ‘b’ and ‘c’ with at most one ‘b’ and two ‘c’s allowed.

Solution: 

Input : n = 3 
Output : 19 
Below strings follow given constraints:
aaa aab aac aba abc aca acb acc baa
bac bca bcc caa cab cac cba cbc cca ccb 

Input  : n = 4
Output : 39

2. What is the algorithm used for graph traversal?

DFS (Depth-first search) and BFS (breadth-first search) are efficient algorithms used for graph traversal.

3. What is a binary search tree?

A binary search tree is a rooted data structure where internal nodes store a key greater than all the keys in the node's left subtree and less than those in its right subtree.

4. How to represent binary search by doing array implementation?

By using one dimensional (1-D  array) array to represent a binary tree.

5. In Java programming language explain the difference between static, constant, and final.

Constant variables never change from their initial value while static variables are initialized only once at the start of the execution and are stored in static memory. The final keywords are when you can't change the value assigned to the variable.

6. What is 'dead beef'?

Dead beef is a hexadecimal value used for debugging the mainframe indicating the deadlock or software crash in the embedded systems. 

7. How to sort 1 million arrays of integers efficiently?

By using the counting sort algorithm which takes advantage of knowing the range of the numbers in the integer array to be sorted (array A).

8. What algorithm is used to find a word in a dictionary?

Aho-Corasick string matching algorithm is used to find a word in a dictionary. 

9. What’s 2 to the power of 64?

2*64 = 2 × 2 × 2 × 2 × … 64 times = 1.8446744e+19.

10. What is the use of the hashcode method in Java?

It helps the program to run faster and facilitates quick access to the data stored.

11. How to reverse only vowels in a string?

This can be done using stack in the following manner:

• Store all the vowel characters in a set.
• Create a stack and push all vowel characters present in the input string from left to right.
• Now again traverse the string for each character. ...
• Return the converted string.

12. Explain Linux virtual memory.

Linux supports virtual memory, that is, using a disk as an extension of RAM so that the effective size of usable memory grows correspondingly. The kernel will write the contents of a currently unused block of memory to the hard disk so that the memory can be used for another purpose.

13. How would you implement a thread-safe LRU cache?

A concurrent LRU cache that supports getting put and the eviction of old keys is implemented. The data structures of ConcurrentLinkedQueue and ConcurrentHashMap are utilized in this process. We use a hashmap as well as a doubly linked list as the data structures that we employ in the implementation of an LRU cache. The eviction order can be maintained with the assistance of a doubly linked list, and an O(1) lookup of cached keys can be achieved with the assistance of a hashmap.

14. How would you go about generating a random sequence of numbers for the lottery?

At the moment when a request for just a lottery ticket was submitted, the computer should use some data, including the computer's real-time clock with accuracy to a millisecond, to activate a procedure that generates five numbers one and Powerball number. This method is known as a lottery draw.

15. How could an internet client/server structure work?

Client-server architecture refers to the design of a computer network wherein a large number of clients (remote processors) ask for something and receive service from a single, centralized server (host computer). Client computers offer a user an interface that enables them to make customer inquiries to a server or view the results that are provided by the server. Client computers are also known as "front ends."

16. How would you find the longest substring which contains only two unique characters?

Perform a loop starting at I = 0 and continuing until N – 1 and think about each visited array. Start an inner loop that goes from j = I + 1 to N – 1, and while it's running, check to see if the current character, S[j], has been seen before. If the condition is met, you should exit the loop and proceed to the next window. If this is not the case, the current character should be marked as visited, as well as the length should be increased to j minus I plus 1.

17. What is multithreaded programming?

The term "multithreading" refers to the capability of a computer program or operating system to support more than one user at the very same time without the need for several instances of the program to be active on the device. The same person can make many requests, as well as multithreading, and can handle all of them.

18. How do you think digital marketing will change in the next five years?

When it comes to digital marketing, the one thing that the future has in store for the sector is an expansion in both need and potential. Every company is rapidly transitioning to online marketing, and digital marketing is all set to play a crucial role in this. Businesses can use digital marketing to target audiences based on various factors like gender, age, location, interests, and education.

19. Can you design a mobile social productivity app for a chain of local orthodontist offices?

Yes, I can do it with reliable tools and a team of experts who can assist me. I will be able to deliver such an app within 20-25 days.

20. Do you think Google should be charging for its productivity apps (Google Docs, Google Sheets, etc.)? Why or why not?

Google doesn't charge anything for normal users which is good. This is compensated by charging the new businesses that sign up for Google Apps. They pay almost USD5 per user per month or USD 50 per customer per year. This means that a company with eight employees that use Google Apps will incur an expense of USD 400 each year. 

21. What is random function RAND?

RAND returns an evenly distributed random real number greater than or equal to 0 and less than 1.

22. How do you transfer cookies to the HTTP protocol?

Ans: For transferring the cookies to HTTP protocol add the "Cookie: name=value" header to your request. 

23. How is a global variable different than local variables?

You can access global variables globally in the complete program, and access to local variables is only within the function.

24. Which data structure is used to manage memory?

Heap data structure is used for memory management.

25. Do you know the size of the C structure below on a 32-bit system? And on a 64-bit machine?

The size of the C structure on a 32-bit is 4 bytes and on a 64-bit machine is 8 bytes.

26. Which regular expression matches an Email id?

A Simple regular expression regex ^(. +)@(\S+)$  matches an email address.

27. Given an array, find the contiguous subarray with the largest sum. (In Dynamic Programming)

Start an iteration for I that goes from 0 to n minus 1, where n is the number of elements in the array.

Now that we have reached this point, we are going to execute a nested loop for j that ranges from I to n minus one and add the value of the element located at index j to a variable called currentMax.

In the end, we will examine each subarray to determine whether or not the currentMax represents the greatest sum of all adjacent subarrays.

28. Find the minimum spanning tree of a connected, undirected graph with weighted edges.

• main() 
• Start.
• Enter the number of vertices in this field.
• Initialize variables. 
• Determine the edges that are incident on each vertex and have the least amount of weight.
• Create an array containing all of the vertices that are related to the first vertex.

If there is more than one component, this indicates that the minimum spanning tree has still not been constructed, and the situation becomes more complicated.

Open-ended or puzzle-based Google interview questions

29. Why are manhole covers round?

The round cover can’t slip through smaller openings so it never falls inside the hole. Also, in round manhole covers, no angles for the alignments are required, and it is easy to handle for pulling off and putting back. 

30. For cleaning all windows in Seattle, what should you charge?

The trick to answering such Google interview questions is to provide an easy and rational answer. For example, you can say USD 10 per window. 

31. How many golf balls can fit in a school bus?

Put 85 inches radius with a heavier ball. Divide that 2.5 cubic inches into 1.6 million and you come up with 660,000 golf balls.

32. How many piano tuners are there in the entire world?

On average, there are approximately 1500 pianos per station for piano tuning. Given this figure, it can be calculated using the number of pianos in the world and the figure 1500. At present, it stands somewhere around 11000 odd piano tuners in the world. 

33. How many times a day do a clock’s hands overlap?

In a day, at each lap of 65 minutes, both the hands of the clock overlap. Keeping this in mind, it happens 22 times throughout the day.

34. How would you boost the Gmail subscription base?

To increase the subscription base for Google I would try and curate a custom strategy to maximize lead generation for Gmail. To answer this question, I would like to draw your attention to a campaign I developed for Google for a client to increase their customer base by a great margin of 22%. I will be looking into researching what attracts the target audience best and experimenting with multiple strategies to see which helps us receive positive results.

35. Out of the series equation of 0,1,1,2,3,4,5,9,13, and 22, which is the odd one out?

As can be seen from the series above, all the succeeding numbers are the sum of itself and the number before it. However, number 9 has no contribution to this equation and thus is the odd one out.

36. How will you get an answer of 1000 if you add only 8 together?

To be able to achieve 1000 as the final answer using just the number 8, you will first have to add the number 8 alone three times and then add 88 to the sum, and then move on to adding 888 to the final answer. The equation is as follows.

8+8+8= 24 + 88= 112 + 888= 1000

37. While looking at a clock if the time is 3:15, what is the angle between the hour’s hand and the minute hand?

Given how a clock has 360 degrees as it is a complete circle if the time is 3:15, the angle between the two is 7.5 degrees. 

 Ad Services Google interview questions

38. How much money do you think Google makes daily from Gmail ads?

You need to have a rough idea about Google and its services to answer such Google interview questions. The answer to this question is about 100 million per day through AdWords.

39. Explain how Google Adwords works.

Google AdWords is designed to help companies target 2 categories of networks, display, and search. With the help of a search network, businesses pick and bid on all the relevant keywords that resonate with their target audience. On the other hand, a display network allows businesses to display their ads to all users who are interacting with their chosen keywords for specific targeting. 

40. What should be the ideal quality score for AdWords?

Quality is very important to ensure the maximum effectiveness of the used Google AdWords. Therefore, the ideal quality store for Google AdWords is between 8 to 10.

Google Interview Questions: HR round

41. Where do you see yourself in 5 years?

42. Why do you want to join Google? Give three reasons.

43. Tell me about the time you had to change yourself.

44. If you are in a coffee shop with Sundar Pichai, what would you talk to him about?

45. Tell us what you know about Google's history

46. Tell me about a time in which you had to navigate ambiguity.

47. Tell me what you are most passionate about.

48. Tell me a time when you had to "sell" or propose a solution to a stakeholder team.

49.​ If I open your browser history, what will I learn about your personality?

50. Which Google product should retire as per you?

Interview Preparation Tips

Found the above Google interview questions helpful? Here are some interview preparation tips that will help to further amp up your preparation level. 

• Keep 3-4 incidences ready about your technical experiences, and don't forget to include attributes that make you an excellent software engineer (superior communication skills, rapid learning ability, strong team player, etc.) if you're applying as a software engineer.
• For practicing coding problems, there is no shortcut or magic wand. So practice well. 
• Coding rounds are timed, so it is important to prepare accordingly. It will be significantly less stressful during the actual interview if you are used to working under time constraints.
• Recognize the most prevalent pitfalls. When it comes to Google interview questions for coding, there are three major traps to avoid: not understanding the Big-O complexity of an algorithm, not understanding Google's expectations, and not expressing your problem-solving method. As you work, keep these hazards in mind.
• Coding on compilers is way different than solving on paper or board. So practice by writing the codes using pen and paper.
• DSA is one of the most important topics in the Google interview questions. Practice it daily for at least a month before your interview. You can find tons of practice questions on various topics on our website. 
• Take proper sleep and relax on the final day before the interview. During the video interview, ensure that your camera is placed properly in a clean room.
• Research well about the company, its products, and its services. This will also help you to pre-decide what questions you would ask them after the interview.
• Practice with ex-interviewers - It would be excellent if you know a software engineer who has conducted interviews at Google or another major tech firm. If not, attend mock interviews to improve your confidence level. 
• The last and most important tip is to Get to know Google's culture. The majority of candidates fail to accomplish so. However, before you spend hours preparing for an interview with Google, be sure it's the appropriate fit for you. Because Google is so prominent, it's easy to jump to the conclusion that you should apply without thinking things through. Talk to people who work at Google or have worked there in the past to get a sense of the culture.

About Google 

Google is one of the most significant Information Technology companies out of the major tech companies in the world which are Meta, Amazon, Microsoft, and Apple. The Company works to make futuristic technological innovations and solve problems to make human lives easier. It has its headquarters based in Silicon Valley, California.

In India, Google has four offices in the big IT hubs 

• Mumbai Maharashtra
• Hyderabad  Andhra Pradesh
• Gurgaon Haryana
• Bangalore Karnataka

Hope this article helped to clear most of your doubts. For more such articles, stay tuned to Unstop!

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