Front End Developer Interview Questions and Answers for Interview Preparation
The hiring managers of FAANG and tier-1 tech companies frame Front End Developer Interview Questions to look for ??in-depth knowledge of HTML5, understanding of website design principles, testing, debugging, and advanced problem-solving skills. Practicing front end interview questions related to these topics will help you ace your tech interview.
If you're a front end developer, software engineer, coding engineer, engineering manager, or tech lead preparing for a tech interview, check out our technical interview checklist, interview questions page, and salary negotiation e-book to get interview-ready!
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So, to uplevel your interview prep, you must brush up on your technical as well as soft skills. Read on for some important front end developer interview questions and answers.
Here's what we'll cover:
- Common Front End Developer Interview Questions and Answers
- CSS Front End Developer Interview Questions and Answers
- HTML Front End Developer Interview Questions and Answers
- More Sample Front End Developer Interview Questions for Practice
- FAQs on Front End Developer Interview Questions
Common Front End Developer Interview Questions and Answers
Here are the most popular front end developer interview questions on webpage and web applications that will help you with your upcoming FAANG interview and every other tech interview.
Q1. How do you ensure that your website or web application is user-friendly?
It is one of the most crucial front end developer interview questions to analyze your understanding of usability and accessibility when designing experiences for end-users.
To ensure that a website/web application is user-friendly:
- Test web applications on various browsers and devices and check whether the experience is usable on all.
- Use popular screen reading software to see whether it is accessible for all users.
- Effective, consistent navigation.
- Review website using automated accessibility assessment tools.
Q2. What resources do you prefer to learn about the latest front end development trends and design?
A hiring manager explores soft skills involving inquisitiveness through such front end developer interview questions. Be specific in your answer.
The best ways to learn about the latest trends in web development are:
- Enrolling in continuing education workshops or online courses
- Participating in StackOverflow forums
- Subscriptions to front end development magazines
Q3. What are the best techniques you have used to increase the performance of a new website?
The most rewarding techniques to improve website performance are:
- Cleaning up excess plugins
- Upgrading web hosting plan
- Enabling Leverage browser caching
- Decreasing HTTP requests
- Enabling GZIP compression
- Optimizing images
- Changing website theme
Q4. What is a version control system? Which VCS are you familiar with?
Front end developer interview questions also include explanations and comparisons of various types of version control systems or VCS. VCS is a software tool that helps software teams manage changes to source code over time.
It is used for all code, files, and assets that multiple team members will collaborate on from all around the world. Thus, it accelerates product delivery. Types of VCS are: Local, centralized, and distributed VCS.
Some popular VCSs are:
- Git (distributed)
- Mercurial (distributed)
- Subversion (centralized)
Q1. What is the difference between let, const, and var?
To get a deeper understanding of the differences between var and let, read this article.
Q4. What is the difference between mutable and immutable objects?
- JS Bin
- JSON formatter and validator
CSS Front End Developer Interview Questions and Answers
Knowledge of advanced CSS is a must to crack front end interviews. Here are some important CSS front end developer interview questions.
Q1. What is a CSS float? State an example of its usage.
A CSS float is a positioning property used with images and layouts. It directs the browser to place a particular element to the right side or the left side of the container. It is useful when a web developer develops a page that dynamically resizes based on the user resolution.
Q2. What is CSS specificity?
Many front end developer interview questions will require you to know about CSS selectors. Through specificity, a browser decides which CSS property values are the most relevant to an element, and they will be applied. CSS specificity refers to the importance of every selector. It is based on the matching rules composed of different sorts of CSS selectors.
Q3. What is FlexBox? What is the use of FlexBox?
Flexbox or Flexible Box is a W3 specified layout system for CSS. It allows the automatic arrangement of responsive elements inside a container depending upon the screen size.
CSS flexbox layout allows:
- Easy HTML formatting
- Makes it simple to align items vertically and horizontally using rows and columns
- Items easily "flex" to different sizes and fill the available space making responsive design easier.
Q4. What is a CSS grid? What is the difference between FlexBox and CSS Grid?
CSS Grid layout is a W3 system for making entire page layouts. It creates complex responsive web design grid layouts easily and consistently across browsers. While Grid is ideal for grids and full pages, flexbox is great for groups of items on a page.
The basic difference between CSS Flexbox and Grid layout is that flexbox allows a one-dimensional layout — either a row or a column. On the contrary, Grid allows a two-dimensional layout — rows and columns simultaneously. Such questions on comparing two items or features are common at front end developer interviews.
Q5. What does the CSS preprocessor do? What are the different CSS preprocessors?
A CSS preprocessor is a program that allows you to generate CSS from the preprocessor's unique syntax. CSS preprocessors compile the code written using a special compiler. Next, they create a CSS file, which the main HTML document can reference. The popular CSS preprocessors are:
Q6. What are pseudo-elements?
Pseudo-elements are certain keywords that allow you to style and specify specific parts of an element rather than the entire thing. For instance, you can style before, the first letter, or the line of a component.
For more CSS questions, check out the top 25 CSS Interview Questions.
HTML Front End Developer Interview Questions and Answers
It goes without saying — you have to be adept at HTML to crack front engineering interviews. Here are some common interview questions on HTML.
Q1. What is the difference between a tag and an attribute?
Here are the main differences:
Q2. What does DOCTYPE do? Is it mandatory?
The DOCTYPE declaration is a mandatory instruction to the web browser. It tells the browser the version of HTML in a webpage, ensuring that the webpage is parsed the same way by various web browsers. Without the DOCTYPE, the browsers enter Quirks Mode.
Q3. What are empty elements in HTML?
An empty element/self-closing element/void element in HTML is the one that cannot have child nodes, i.e., it doesn't have any embedded or text elements. Example: the <br> element, which represents a line break.
Q4. What does semantic HTML mean?
Semantic HTML means using the most appropriate tag for a task. Semantic markup is HTML that introduces meaning to the web page instead of a simple presentation. For example, a <p> tag implies that the enclosed text is a paragraph.
More Sample Front End Developer Interview Questions for Practice
Here are a few more front-end developer interview questions on JS, CSS, HTML, and web design for your practice:
- What are the benefits of using spread syntax, and how is it different from the rest of syntax?
- Give an example for destructuring an object or an array.
- What are the ways to integrate CSS into an HTML page?
- How would you fix browser-specific styling issues?
- What do you know about styling SVG?
- What is the use of the Clearfix CSS property?
- What is progressive rendering?
- Explain the difference between layout, compositing, and painting.
- What are the differences between Long-Polling, Server-Sent Events, and Websockets?
- What are the best tools to find a performance bug in your code?
FAQs on Front End Developer Interview Questions
Q1. How do I prepare for front end developer interview questions?
Q2. What are some must-learn topics for answering front end developer interview questions?
Q3. Do I need to know algorithms and data structures for front end developer interview questions?
Yes. You must know basic algorithms and data structures for front end developer interview questions. Hiring managers expect you to know things like filtering and sorting a data set.
Q4. What front end skills do you require for front end developer interview questions?
Q5. Are front end developer interview questions easy?
Front end developer interview questions might look easy, but they are not that simple. They require a thorough knowledge of various languages and technologies. Therefore, you must have a solid preparation strategy to ensure you cover all ground.
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