Homebreadcumb forward arrow iconBlogbreadcumb forward arrow iconFull Stack Developmentbreadcumb forward arrow iconTop 25 Bootstrap Interview Questions and Answers [For Freshers & Experienced]

Top 25 Bootstrap Interview Questions and Answers [For Freshers & Experienced]

Last updated:
18th Jun, 2023
Read Time
8 Mins
share image icon
In this article
Chevron in toc
View All
Top 25 Bootstrap Interview Questions and Answers [For Freshers & Experienced]

If you are a mobile web developer, you’ve probably already heard of Bootstrap and its significance in building a fast, responsive and aesthetically designed UI. It is the priority of every business today to deliver an intuitive and flexible user interface and user experience (UI/UX). And Bootstrap helps you do just that! 

Since businesses are keen on developing an adjustable front-end design for devices of varied screen sizes, being skilled at Bootstrap today is worth a huge paycheck. 

So, if you are starting a technical career or are eyeing a higher-up position, here are some of the most commonly asked Bootstrap interview questions and answers to help you land that dream job. So, without further ado, let’s get started!

Check out our free courses to get an edge over the competition. 

Ads of upGrad blog

Tips for Demonstrating Bootstrap Proficiency in Interviews

When preparing for Bootstrap interview questions for freshers, it’s essential to showcase your proficiency in this popular front-end framework effectively. Here are some valuable tips for demonstrating Bootstrap proficiency in interviews:

  • Hands-on Projects: Build practical projects, such as responsive websites or web applications, using Bootstrap. Highlight these projects in your portfolio and discuss them confidently during the interview.
  • Code Samples: Prepare well-commented Bootstrap code samples that highlight different aspects of the framework. Discussing these code samples will demonstrate your understanding of Bootstrap’s syntax and capabilities.
  • Problem-solving Skills: Be prepared to solve problems that require the application of Bootstrap concepts. Practice common challenges and demonstrate your ability to find creative solutions.
  • Responsive Design Expertise: Showcase your understanding of responsive design principles facilitated by Bootstrap. Discuss techniques like media queries, mobile-first design, and Bootstrap’s responsive utilities.
  • Component Usage: Be well-versed in the usage and customization options of Bootstrap’s components. Discuss scenarios where you’ve utilized specific components effectively.
  • Bootstrap Customization: Discuss how you’ve customized Bootstrap in previous projects. Talk about customizing themes, modifying variables, and leveraging Bootstrap’s SASS to create unique designs.
  • Browser Compatibility: Be prepared to discuss how you ensure cross-browser compatibility in your projects. Share experiences troubleshooting and resolving browser-specific issues.
  • Stay Updated: Keep up with the latest Bootstrap version and its new features. Be prepared to discuss how these updates have impacted your development workflow or enhanced your projects.

Common Mistakes to Avoid in Bootstrap Interviews 

Navigate your Bootstrap job interview successfully by steering clear of common pitfalls. Learn essential tips and insights to sidestep common errors and present yourself as a strong candidate for Bootstrap web development roles.

  • Ignoring Accessibility: Accessibility is a crucial aspect of web development, and Bootstrap offers features and best practices to ensure websites are accessible to all users. Ignoring accessibility considerations during the interview may raise concerns about your attention to detail and inclusive design practices. Be prepared to discuss accessibility features in Bootstrap and demonstrate your commitment to creating accessible web experiences.
  • Inadequate Knowledge of Bootstrap Documentation: Bootstrap has comprehensive documentation that covers all its features and usage guidelines. Failing to study and understand the documentation can lead to missed opportunities to showcase your knowledge. Take the time to thoroughly review the official Bootstrap documentation to ensure you are well-versed in its capabilities and best practices.
  • Poor Problem-solving Skills: Bootstrap interviews often include problem-solving questions that require applying Bootstrap concepts to real-world scenarios. Inadequate problem-solving skills or the inability to think critically may reflect negatively on your ability to work effectively with Bootstrap. Practice solving coding challenges and brainstorming solutions to improve your problem-solving skills.
  • Lack of Confidence and Communication: Confidence plays a vital role in interviews. Failing to communicate effectively or express confidence in your understanding and experience with Bootstrap may give the impression that you are not well-prepared or lack confidence in your abilities. Practice articulating your thoughts clearly and concisely to ensure a confident and effective interview performance.
  • Over Reliance on Pre-built Templates: While Bootstrap provides a wide range of pre-built templates and components, it’s important not to rely solely on them. Interviewers may want to assess your ability to customize and adapt Bootstrap to specific project requirements. Showcase your skills in customizing Bootstrap components and creating unique designs to avoid being seen as someone who only relies on out-of-the-box solutions.

Top 25 Bootstrap Interview Questions and Answers

Question 1: What is Bootstrap?

Bootstrap is a highly responsive and easy-to-use front-end framework used to create web applications with HTML, CSS, and JS. It has a quick and intuitive layout for the benefit of its users. Bootstrap allows users to build crisp and aesthetic user interfaces for mobile applications using existing design templates. Its features include Dropdown menus, Buttons, Forms, Glyphicons and Alerts Tab, to name a few.

Check out upGrad’s Advanced Certification in DevOps

Question 2: What are the Key Components of Bootstrap?

Bootstrap is loaded with a number of components that make way for an excellent user experience. These include interactive features like pop-ups, dropdown menus, navigation bars, buttons, forms, alerts, etc.

Following are the key components of Bootstrap:

  1. JS Plugins: this is where JS and jQuery plugins are
  2. Customize: used to customize frameworks
  3. CSS: includes CSS files
  4. Scaffolding: contains a grid system, background styles, etc

Check out upGrad’s Advanced Certification in Cloud Computing

Question 3: What Makes Bootstrap an Effective Option for Mobile and Web Development?

Bootstrap’s quick and easy to use layout allows for faster development of mobile and web applications. The design templates included are highly responsive and automatically adjust themselves to different screen sizes without any compromise to the essence of a webpage.

Question 4: What are the Various Features of Bootstrap?

Following are some features of Bootstrap:

– It is a free, open-source platform; allows developers to contribute to its improvement. 

– Bootstrap is fast, responsive and extremely easy to use

– It is compatible to use with all browsers

– Bootstrap has a rich library of designs and templates to choose from

Question 5: What are Glyphicons?

Glyphicons in Bootstrap are font-formatted icons that are used to denote actions like a warning, delete, zoom, edit, etc. There are about 200 such icons contained in an individual class. 

The syntax to use these glyphicons is:  

<p><span class = “glyphicons glyphicon-pencil”></span></p>

Explore Our Software Development Free Courses

Question 6: Explain Dropdowns and Button Groups in Bootstrap. 

A dropdown is a dynamic toggle menu that contains a list of linked items under it. It is one of the cleanest design elements of a website. 

The syntax to use these Dropdowns is:

<div class= “dropdown”><!– have your list in this with the class .dropdown-menu –></div>

Button Groups are a series of buttons placed in an adjacent manner. This Bootstrap component requires that division elements with .btn-group class be defined first. After that, the button elements are nested using.btn class.

The syntax is as follows:

<div class=“btn-group”><button class= “btn”>Correct</button></div>

<div class=“btn-group”><button class= “btn”>Wrong</button></div>

Using the above two components, you can create a new component called the Button Dropdown that would enable you to trigger a dropdown using a button element. 


<button class = “btn-default dropdown-toggle”><!— the dropdown component goes here –></button>

Explore our Popular Software Engineering Courses

Question 7: What are Input Groups? 

Input groups is an extension to the form-control class that allows you to add a text string or include buttons on one of the sides of an input field. 

The .input-group class and .input-group-addon class are used together to implement an Input Group. 


<div class=”input-group”>

<span class=”input-group-addon” id=”basic-addon1″>@</span>

<input type=”text” class=”form-control” placeholder=”Username” aria-describedby=”basic-addon1″>


Question 8: What are the Four Contextual Classes to Use with Bootstrap’s Progressive Bar.

Following are the four contextual classes that are used with Bootstrap’s progressive bar:

  1. Progress-success
  2. Progress-info
  3. Progress-warning
  4. Progress-danger

Question 9: How Many Different Button Styles are there in Bootstrap? What are They?

There are 7 different styles in which the Bootstrap button can be used. They are as follows: 

  1. .btn-info
  2. .btn-warning
  3. .btn-danger
  4. .btn-success
  5. .btn-link
  6. .btn-primary
  7. .btn-default

In-Demand Software Development Skills

Question 10: Explain Bootstrap Alerts.

Bootstrap alerts are used in the creation of presuming alert messages. This is done mainly to style the messages so they can appear more noticeable to a user.

Following are the four classes in alerts:

  1. .alert-success
  2. .alert-info
  3. .alert-warning
  4. .alert-danger.

Question 11: How do you Create a Vertical or Basic Form in Bootstrap?

Following are the steps to create a vertical basic form in Bootstrap: 

Step 1: To the parent <form> element, add a role form.

Step 2: Add labels and controls inside a <div> with class.form-group

Step 3: Add the .form-control class to every text URL <input>, all <textarea> as well as  <select> elements. 

upGrad’s Exclusive Software Development Webinar for you –

SAAS Business – What is So Different?


Question 12: What is Pagination in Bootstrap?

As the label suggests, Pagination allows you to split the contents of your website into different pages to ease navigation. 


<ul class = “pagination”><!—List elements goes here –></ul>

Question 13: What is a Bootstrap Container?

The bootstrap container is essentially a container to add an HTML code. This container site then becomes a part of the page where the content can be added. This makes your UI faster and more responsive. 

Also Read Bootstrap vs Material UI

Question 14: List Any Three Components of Bootstrap. 

  1. Navbar: acts like a header for navigation on your website

Syntax: <nav class = “navbar”><!—Code your navigation DOM elements –></nav>

  1. Jumbotron: behaves like a viewport; can assume full screen to concentrate on a key content

Syntax: <div class = “jumbotron”><!—Write your content within DOM elements here –></div>

  1. Progress bars: displays feedback highlighting the progress of an action

Syntax: <div class=”progress-bar” role=”progressbar” aria-valuenow=”60″ aria-valuemin=”0″ aria-valuemax=”100″ style=”width: 60%;”>

Question 15: What are the Two Types of Layouts in Bootstrap?

  1. Fluid Layout
  2. Fixed Layout

Question 16: What is Fluid Layout? 

Fluid Layout is a useful feature when the total width of the screen needs to be used in the design. When you choose this option, the layout adjusts itself as per the browser size.

Question 17: What is the Fixed Layout? 

A Fixed Layout is different from the Fluid Layout such that it doesn’t adjust itself as per the size of the browser. However, it is still fast and responsive at 940px. 

Question 18: What is the Modal Plugin in Bootstrap?

An inherited window placed as a layer over the parent window is known as the Modal window. This window adds value to the user experience by making it functional. The plugin used to create Modal windows is called the modal plugin.

Question 19: What are the Bootstrap Collapsing Elements?

You can collapse any Bootstrap element without JavaScript code. This can be done by adding data-toggle= ”collapse” to the controller element. The data-target is also included to give it control to collapse the element. 

To use this Bootstrap feature, use .collapse(options).

Read our Popular Articles related to Software Development

Question 20: Define a Bootstrap Well?

Bootstrap well is similar to the Bootstrap container and helps the content look more suppressed and clean on the page. It can also be used to wrap the content by adding .well class.

Question 21: What is the Carousel Plugin in Bootstrap.

The Carousel Plugin allows you to create sliders on your web pages. Sliders allow large blocks of contents to be recessed to a small space on the page. 

A few carousel plugins you can use are: 






Question 22: Explain the Output of the Following Code.

<div class=”progress”>

<div class=”progress-bar progress-bar-success” style=”width: 65%”>

<span class=”sr-only”>75% successfully completed</span>


<div class=”progress-bar progress-bar-warning” style=”width: 20%”>

<span class=”sr-only”>30% completed with warnings</span>


<div class=”progress-bar progress-bar-danger” style=”width: 15%”>

<span class=”sr-only”>15% did not complete</span>



Answer: The output of the above code would show a full width and fully populated result on the progress bar. This is because Bootstrap piles multiple bars into a single bar when placed in the same progress parent element. Also, the total progress bar sum is 100%. 

Learn Software Development Courses online from the World’s top Universities. Earn Executive PG Programs, Advanced Certificate Programs or Masters Programs to fast-track your career.

Question 23: State the Codes used for Code Display in Bootstrap?

Answer: There are two codes used for code display. They are:

  1. <code> tag 
  2. <pre> tag

Question 24: Explain Normalize in Bootstrap. 

Bootstrap normalize is a feature on Bootstrap using which a small CSS file is employed to increase cross-browser consistency.

Question 25: What is the Method to Customize Links of Pagination in Bootstrap?

Use .disabled for links that are not clickable and use .active for referencing the current page.

Checkout: Bootstrap vs Material UI

Ads of upGrad blog

Learn Software Courses online from the World’s top Universities. Earn Executive PG Programs, Advanced Certificate Programs, or Masters Programs to fast-track your career.


We hope these questions and answers helped you brush up on your knowledge of Bootstrap. Good luck with that interview!

If you’re interested to learn more about full-stack software development, check out upGrad & IIIT-B’s Executive PG Program in Full-stack Software Development which is designed for working professionals and offers 500+ hours of rigorous training, 9+ projects and assignments, IIIT-B Alumni status, practical hands-on capstone projects & job assistance with top firms.


Rohan Vats

Blog Author
Software Engineering Manager @ upGrad. Passionate about building large scale web apps with delightful experiences. In pursuit of transforming engineers into leaders.

Frequently Asked Questions (FAQs)

1What is a bootstrap library?

Bootstrap is a collection of tools for creating websites, mobile apps and web apps. It is available via CDN and npm. Bootstrap is fully responsive, mobile first library. Bootstrap is a free and open-source project, licensed under Apache 2.0. Bootstrap has been used successfully by many companies, large and small. Bootstrap is a collection of tools that can be used to kickstart a project. It contains front end styling components and some jQuery plugins that can be used to speed up the development process.

2What are the various features of bootstrap?

Bootstrap is an open-source framework for designing web sites and web applications. It contains html and css based design templates for formatting contents. Some of the important features of bootstrap are: It provides responsive web designs. It provides interactive website templates. There are no java script dependencies. It has standard HTML and CSS code. It is an open-source framework.

3What is front-end programming?

Front-end programming is a process of adding dynamic content to a web page. This can include interactive features such as form validation, or simple elements like animations and background effects. Front-end web development relies on languages such as HTML and CSS, which are designed for creating pages, formatting content, and styling the page's presentation. The server-side, on the other hand, uses programming languages such as PHP or Ruby, which enable the creation of dynamic pages with complex functionality.