The mere mention of whiteboard coding can send shivers down the spine of even the most experienced developers. Standing in front of a blank whiteboard with a marker in hand, trying to solve a complex algorithm while interviewers scrutinize your every move is undoubtedly stress inducing. Yet, this practice remains a staple in technical interviews at many companies, particularly at larger tech organizations.

But is whiteboard coding still relevant in today’s remote work environment? And if so, how can you effectively practice this skill to succeed in technical interviews? In this comprehensive guide, we’ll explore the continued relevance of whiteboard coding and provide actionable strategies to help you master this challenging interview format.

Table of Contents

What is Whiteboard Coding?

Whiteboard coding is an interview technique where candidates are asked to solve programming problems by writing code on a whiteboard instead of using a computer. This approach focuses less on syntax perfection and more on problem solving abilities, algorithm design, and communication skills.

The traditional whiteboard coding interview typically follows this format:

  1. The interviewer presents a problem or algorithm challenge
  2. The candidate thinks through the problem out loud
  3. The candidate writes their solution on the whiteboard
  4. Throughout the process, the candidate explains their thought process
  5. The interviewer may ask follow up questions or request optimizations

Unlike coding on a computer, whiteboard coding doesn’t offer the luxuries of syntax highlighting, auto completion, or the ability to run and test your code. It’s a raw demonstration of your problem solving abilities, algorithmic thinking, and communication skills.

Is Whiteboard Coding Still Relevant?

With the rise of remote work and virtual interviews, many wonder if whiteboard coding is becoming obsolete. The short answer: whiteboard coding remains relevant, though its format has evolved.

Why Whiteboard Coding Persists

Despite criticism, whiteboard coding continues to be used in technical interviews for several reasons:

The Evolution of Whiteboard Coding

While traditional in person whiteboard interviews haven’t disappeared, they have evolved:

Despite these evolutions, the core skills being assessed remain the same: problem solving, algorithmic thinking, code organization, and communication.

Which Companies Still Use Whiteboard Coding?

Whiteboard coding (or its virtual equivalent) is still common at:

However, there’s a growing movement of companies moving away from traditional whiteboard interviews toward more practical, job relevant assessments. Companies like Basecamp, Automattic, and GitLab often focus more on portfolio reviews, take home projects, and paid trial periods.

How to Practice Whiteboard Coding Effectively

Whether you’re preparing for a traditional whiteboard interview or its virtual counterpart, effective practice is essential. Here’s a comprehensive approach to honing your whiteboard coding skills:

1. Master the Fundamentals

Before diving into whiteboard practice, ensure you have a solid grasp of:

Resources like “Cracking the Coding Interview” by Gayle Laakmann McDowell, “Introduction to Algorithms” by Cormen et al., and online courses from platforms like Coursera and edX can help strengthen your foundation.

2. Create a Realistic Practice Environment

To simulate the interview experience:

If you don’t have access to a physical whiteboard, alternatives include:

3. Follow a Structured Problem Solving Approach

Develop and consistently practice a structured approach to problem solving:

  1. Understand the problem: Clarify requirements, constraints, and edge cases.
  2. Work through examples: Trace through simple examples to understand the expected behavior.
  3. Brainstorm approaches: Consider multiple solutions before coding.
  4. Analyze complexity: Discuss time and space complexity of your proposed solution.
  5. Write pseudocode: Outline your approach before writing actual code.
  6. Implement the solution: Write clean, readable code.
  7. Test your code: Walk through your solution with test cases, including edge cases.
  8. Optimize if needed: Discuss potential improvements.

4. Practice Regularly with a Variety of Problems

Consistent practice is key to improvement:

5. Find a Practice Partner or Group

Practicing with others offers several benefits:

You can find practice partners through:

6. Focus on Verbalization and Communication

A crucial aspect of whiteboard coding is explaining your thought process:

7. Learn from Each Practice Session

After each practice session:

Adapting to Virtual Whiteboard Interviews

With remote work becoming more common, virtual whiteboard interviews have gained popularity. Here’s how to adapt your practice for this format:

Familiarize Yourself with Common Tools

Practice using tools that companies frequently use for virtual coding interviews:

Spend time getting comfortable with these platforms before your interviews. Learn keyboard shortcuts and features that can help you code more efficiently.

Set Up Your Environment

Create an optimal virtual interview environment:

Practice Screen Sharing and Typing

Virtual interviews often require different skills:

Common Whiteboard Coding Challenges and How to Overcome Them

Whiteboard coding comes with unique challenges. Here’s how to address them:

Performance Anxiety

Challenge: Many candidates experience heightened anxiety during whiteboard interviews, which can impair their problem solving abilities.

Solutions:

Time Management

Challenge: Balancing thorough problem exploration with timely solution implementation.

Solutions:

Handwriting and Space Management

Challenge: Writing legible code and managing limited whiteboard space.

Solutions:

Syntax Without Auto Complete

Challenge: Writing syntactically correct code without IDE assistance.

Solutions:

Handling Mistakes

Challenge: Dealing with errors or wrong approaches during the interview.

Solutions:

Alternatives to Traditional Whiteboard Coding

As the tech industry evolves, some companies are adopting alternative assessment methods. Familiarize yourself with these formats as well:

Take Home Coding Assignments

Many companies now provide candidates with a project to complete on their own time:

Pair Programming Interviews

In this format, you collaborate with an interviewer on a coding task:

System Design Interviews

Especially common for senior roles, these focus on designing larger systems:

Portfolio Reviews

Some companies evaluate candidates based on previous work:

Whiteboard Coding on Interview Day: A Step by Step Approach

When the actual interview arrives, follow this structured approach:

Before You Start Coding

  1. Listen carefully to the problem: Take notes if necessary.
  2. Ask clarifying questions:
    • What are the input constraints?
    • How should I handle edge cases?
    • What’s the expected output format?
    • Are there performance requirements?
  3. Work through examples: Use simple test cases to confirm your understanding.
  4. Think aloud: Share your initial thoughts about potential approaches.
  5. Discuss tradeoffs: Consider multiple solutions and their pros/cons.

During Coding

  1. Start with a high level approach: Outline your solution before diving into details.
  2. Write clean, readable code: Use consistent indentation and meaningful variable names.
  3. Explain as you go: Narrate what you’re doing and why.
  4. Manage your space: Plan your whiteboard layout to avoid cramming.
  5. Stay calm if you get stuck: Vocalize your thought process and consider stepping back to reevaluate.

After Coding

  1. Test your solution: Trace through your code with example inputs.
  2. Check edge cases: Empty inputs, single elements, maximum values, etc.
  3. Analyze complexity: Discuss the time and space complexity of your solution.
  4. Suggest optimizations: Mention potential improvements even if you don’t implement them.
  5. Ask for feedback: Show willingness to learn and improve.

Sample Dialogue for a Whiteboard Coding Interview

Here’s how a well executed whiteboard coding interview might sound:

Interviewer: “Write a function to find the first non repeating character in a string.”

Candidate: “Let me make sure I understand the problem correctly. I need to find the first character in the string that appears exactly once, correct? For example, in the string ‘aabccd’, the first non repeating character would be ‘b’. Is that right?”

Interviewer: “Yes, that’s correct.”

Candidate: “And what should I return if there are no non repeating characters? Should I return null, an empty string, or something else?”

Interviewer: “Return null in that case.”

Candidate: “Great. Let me think about approaches. The straightforward way would be to count occurrences of each character and then scan the string again to find the first character with a count of 1. This would be O(n) time complexity where n is the length of the string.

Let me code this up. I’ll use a hash map to store the counts:”

function firstNonRepeatingChar(str) {
  if (!str || str.length === 0) return null;
  
  // Count occurrences of each character
  const charCount = {};
  for (let char of str) {
    charCount[char] = (charCount[char] || 0) + 1;
  }
  
  // Find the first character with count 1
  for (let char of str) {
    if (charCount[char] === 1) {
      return char;
    }
  }
  
  // No non-repeating character found
  return null;
}

Candidate: “Now let me test this with a few examples. For input ‘aabccd’, we first count: ‘a’:2, ‘b’:1, ‘c’:2, ‘d’:1. Then we scan the string again and find ‘b’ as the first character with count 1, so we return ‘b’.

Let’s try another example: ‘aabb’. We count: ‘a’:2, ‘b’:2. When we scan again, no character has a count of 1, so we return null.

For edge cases, if the input is null or an empty string, we return null as specified.

The time complexity is O(n) where n is the length of the string, as we iterate through the string twice. The space complexity is O(k) where k is the number of unique characters in the string, which in the worst case is O(n) if all characters are unique.”

Resources for Whiteboard Coding Practice

To support your practice, here are valuable resources categorized by type:

Books

Online Platforms

Courses

YouTube Channels

Mock Interview Services

Conclusion: Embracing the Whiteboard Challenge

Whiteboard coding remains a significant part of the technical interview landscape, even as it evolves in the era of remote work. Rather than viewing it as an artificial or outdated practice, consider it an opportunity to demonstrate not just your coding abilities, but your problem solving approach, communication skills, and grace under pressure.

The skills you develop while practicing whiteboard coding extend far beyond interview success. The ability to break down complex problems, consider multiple approaches, communicate technical concepts clearly, and write clean code without relying on tools are valuable in everyday engineering work.

Remember that interviewers are often less concerned with perfect solutions and more interested in your problem solving process. They want to see how you think, how you communicate, how you handle challenges, and how you respond to feedback.

With deliberate practice using the strategies outlined in this guide, you can transform whiteboard coding from a source of anxiety into a showcase for your technical abilities. Start small, practice consistently, seek feedback, and gradually tackle more complex problems.

Whether your next interview features a physical whiteboard, a virtual coding environment, or an alternative format, the fundamental skills remain the same: understand the problem, communicate your thinking, implement a solution methodically, and verify your work.

Approach each practice session and interview as an opportunity to learn and improve. With time and dedication, you’ll develop not just the ability to solve problems on a whiteboard, but the confidence to do so with poise and clarity.

Good luck with your interview preparation, and remember that each whiteboard challenge brings you one step closer to mastery!