Top 44 Web Development Interview Questions For 2022

Last Updated on: September 5, 2022

Becoming a web developer is one of the trending calls of the era. You code, you design, and you create. Before you step into its technical aspects, you need to prepare yourself with all the relevant skills that go around the subject. Be it a certified Full-stack web development course or self-learning, before getting yourself industry ready to full corporate paradigms, there are certain knowledge basics which you ought to know. Let’s see a few of the must-know questions which your interviewer would expect you to answer before handing you over the role.

Top Web Development Interview Questions and Answers for Freshers

There are some common web developer interview questions. Here are some web development interview questions and answers for freshers:

Q1. What are the key skills that a web developer should know:

Ans: The key technical coding skills that a web developer needs to know are,

1. HTML
2. CSS
3. JavaScript
4. SQL
5. PHP/RUBY/PYTHON
6. JQuery

Q2. What is the difference between SVG and <canvas>?

Ans: <SVG> Scalable vector Graphic (based on shape) is an image format based on XML which is used to describe 2-dimensional graphics on the web. SVG images can be customised, resized, compressed, and modified using JavaScript and CSS. SVG images can be printed in high resolutions. SVG gives better performance with smaller objects and larger space. SVG images possess better scalability, and pixelation is less likely to occur.

<Canvas> is a Raster based image format (based on pixels). Canvas Images can be interchangeably converted to png and JPEG format. Comparatively to SVG, Canvas images have less rendering capability. Canvas images can only be modified with Javascript but no CSS. Canvas images have lower scalability compared to SVG. They perform better with large no of objects and smaller space.

Q3. Name some Latest APIS included in HTML5.

Ans: Some latest APIS included in HTML5 are

1. HTML Geolocation
2. HTML Drag and Drop
3. HTML local storage
4. HTML Application cache
5. HTML Web workers
6. HTML SSE

Q4. Which APIS has been removed from HTML5 and through elements they have been replaced?

Ans: The following elements have been removed in HTML5:

1. <acronym> is replaced by <abbr>
2. <applet> is replaced by <object>
3. <basefont> is replaced by CSS
4. <big> is replaced by CSS
5. <center> is replaced by CSS
6. <dir> is replaced by <ul>
7. <font> is replaced by CSS
8. <strike> is replaced by CSS, <s> or <dl>
9. <tt> is replaced by CSS

Q5. What is the difference between Detach() and remove() and empty() in JQuery?

Ans: Detach(): This instruction removes all the selected elements, including child nodes and texts. It keeps data and events intact. It saves a copy of removed items which can be reinserted later.

Remove(): This instruction removes elements, including data and events.

Empty (): This instruction only removes the content from the selected element.

Q6. What is the difference between a front end and back end developer?

Ans: Front-end developer: Front end developer is the interface between the design and the user. They are responsible for generating the view of the website through encrypting layouts in terms of the images and graphics and map them into codes. How a website will look at the end of the day can only get fruitful when it gets coded into. Front end developers need to be efficient in at least three languages, HTML, CSS and Javascript. 

Back-end developer: While front end developers deal with the look and feel of the website and convey it to the users, Back end developers do the interfacing between website and server. They build codes which back website server and database systems. 

Their role is very crucial and is rooted since the whole reliability of the website depends on them. Imagine you are trying to reach a website, and it shows “404 error”. Yes, that’s what!. This is how crucial it gets when it comes to the back-end. Basically, these developers use coding languages like Java, Python, Ruby and PHP for the purpose.

Q7. What is the difference between HTML and HTML5?

Ans: HTML is known as HyperText Markup Language used to design a web page. HTML5 is the fifth version of HTML.

HTML: 

• It doesn’t support audio and video with a flash player.
• It generally uses cookies to store data.
• It is compatible with all old browsers.
• It has complicated and long encoding.
• Charset, async and ping are not available in HTML.
• It is less likely to get accurate Geolocation of the user.
• It doesn’t use inaccurate syntax.

HTML5:

• It supports audio and video with <audio> and <video> tags.
• It uses the SQL database and cache to store data.
• It is compatible with all the new browsers like Firefox, Safari, Mozilla.
• It hosts simple and easy encoding.
• Charset, async and ping are a part of its attributes.
• Accurate Geolocation of the user can be tracked using JS Geolocation API.
• It can handle inaccurate syntax.

Q8. Name some web development tools Web developers generally use?

Ans: Some web development tools that front end developers generally use are

• Sublime text
• JQuery
• Angular JS
• Sass
• Grunt
• Codepen
• GitHub
• HTML 5
• Webstorm
• Typescript

Q9. What do you mean by Doctype?

Ans: Doctype is a document type declaration which is basically an instruction which entails the webpage about the markup language that has been used. It informs about which version of HTML has been implemented.

Declaration:

<!DOCTYPE html>

<html>

<head>

<title>Page Title</title>

</head>

<body>

<h1>My First Heading</h1>

<p>My first paragraph.</p>

</body>

</html>

Q10. How is HTML different from XHTML?

Ans: XHTML is the Extensible Hyper Markup Text language.

It is more formal, stringent and disciplined than normal HTML.

• XHTML elements demand to be neatly nested.
• XHTML elements should be closed.
• XHTML elements have to be in lower case.
• In XHTML, attributes minimisation is prohibited.
• In XHTML, the attributes have to be within Quotes.

Q11. What are some effective ways to reduce page loading time?

Ans: Few ways through which you can reduce the page loading time are,

• Reducing the image size: Don’t scale the dimensions, but optimise it.
• Removing Widgets which are not required and preventing it from overstuffing the page.
• By compressing and optimising the content.
• It is preferable to place stylesheet references at the top.
• It is preferable to place Script reference below the page.
• Reducing the usage of HTTP requests.
• Reducing 301 redirects.
• It is preferable to cache the web, to reduce the strain on the servers.

Q12. What Are the Key Responsibilities of Web Developers?

Web developers need to perform a wide range of functions, including:

• Build products by using HTML, CSS, JavaScript, PHP, and other relevant coding languages.
• Design, develop, test and debug applications in such a way that they can work in a cross-platform, and cross-browser environment.
• Coordinate with the programmers and designers for the completion of projects.
• Develop design specifications for optimization of the web programs.
• Identify and fix bugs besides resolving website issues.
• Handle the technical aspects of a website including its cache and performance.
• Provide support with web management best practices.
• Keep track of the latest technology and languages.
• Maintain and update the websites in-line with the modern web standards
• Monitor traffic to a website.

Q13. List the Advantages of HTTP/2 over HTTP 1.1.

HTTP or Hypertext Transfer Protocol allows internet users to exchange information on the World Wide Web or WWW. Since its introduction in 1991, four versions of HTTP have been released with the latest one being HTTP/2.0 which was introduced in 2015 as a major revision to HTTP/1.1. The newer version has several advantages over the earlier one. These include:

Improved Performance – The new HTTP version is designed to speed up page loading while reducing the round-trip time or RTT for resource-intensive websites.

Multiple Resources – The HTTP 1.1 version allowed the managing of webpages by using HTML markups and images, but the new version comes with multiple resources for webpages, including images, fonts, and much more. The earlier version was also not designed to handle a large number of resources.

Multiplexing – The inclusion of multiplexing resolves the head-of-line blocking problems faced with HTTP/1.1. Multiplexing means that multiple requests can be sent between browsers and servers at one point in time thereby ensuring delivery of the several elements of a web page over a single TCP connection.

Header Compression – The new HTTP version can compress HTTP headers to reduce overhead allowing them to be sent between the browser and the server in one trip and over a single TCP connection.

Server Push – HTTP/2 servers can push resources into a browser’s cache even before they are requested. 

Binary Protocols – The use of binary protocols instead of textual ensures that less bandwidth is consumed while reducing the chances of errors.

Q14. Explain CORS (Cross-Origin Resource Sharing) and Write its Importance

Cross-origin resource sharing enables webpages from one domain to have controlled access to resources located in different domains. This means that scripts running on a browser client can interact with and access resources from other origins. The CORS provides flexibility to the Same Origin Policy that restricts a website’s ability to access resources outside its source domain. A website’s CORS policy needs to be strong to avoid cross-domain attacks and cross-origin attacks like Cross-site Request Forgery or CSRF.

Q15. What Does ETag Mean and How Does it Work?

Etag or entity tag is a mechanism that HTTP provides to validate web caches that allow conditional requests to be made from a browser for resources. The Etags ensure that the simultaneous updates of the same resource do not overwrite each other.

Etags are opaque identifiers assigned by a server to a specific version of a resource found at a specific URL. A new Etag is assigned whenever the resource representation at the URL changes.

Q16. What is Webpack?

Webpack is a tool that bundles JavaScript modules that are reusable chunks of code built from the JavaScript, node modules, images, and CSS styles of an application and packaged for easy addition to a website. Webpack arranges a large number of files of an application into a few based on its dependency graph. The small bundle of files is the bare minimum required to run the application.

Q17. What are the Newly Introduced Input Types, APIs, Form Elements, and Elements That Support Media Content in HTML5.

HTML5 has been updated to include several new input types, APLs, form elements, and elements supporting media content. 

New Input Types include

• Colour
• Date
• Datetime-local
• Email
• Month
• Week

New Form Elements include

• <datalist> 
• <keygen>
• <output> 
• <progress>
• <meter>

New APIs Introduced in HTML5 include

• History API
• Page Visibility API
• Battery Status API 
• User Timing API
• Vibration API

Elements that support Media include

• <audio>
• <video>
• <source>
• <embed>
• <track>

Q18. What is the Difference Between Span Tag and Div Tag in HTML5?

This is among the common web developer interview questions. Both the span and the div tags are used to indicate a part of a webpage. While divs are block-level elements, spans are inline elements.

<span> tag	<div> tag
This tag is used for inline elements and for paragraphs.	This category of tags is used for block-level elements.
This tag is used to highlight any specific word (or a small section of a line) on a webpage.	The div tag is generally used to highlight a section on the webpage.
A specific colour code is used to highlight the HTML content.	Borders with height and width with specified colour pixels are used to highlight the HTML content.
This tag does not support the align attribute and so does not appear on a new line.	This tag supports the align attribute and so does appear on a new line.

Q19. What is HTML5 Web Storage?

An attractive feature of HTML5 is the web storage feature that can be used by web applications to store data locally in the browser on the user/client side. Also called the DOM storage or Document Object Model Storage, the web storage feature allows storing of data in the form of a key/value pair in the user’s browser. Although quite similar to using cookies, web storage is more convenient and faster. It should not be used to store sensitive data since it is not transmitted over the wire and is not encrypted.

Web storage can be: 

Local storage, which stores data with no expiration date. The information stored here is available even after the user’s browser is closed and reopened.

Session storage, which stores data for a single session only. The data is lost or deleted as soon as the user closes the browser.

Can You Explain DOM (Document Object Model)?

The Document Object Model or DOM is a cross-platform, language-independent Application Programming Interface (API) for XML or Extensible Markup language and HTML documents. It describes the logical structure of documents and how to access them through a tree model. The hierarchical structure allows the users to navigate easily.

Q20. What Do You Know About Pair Programming?

Pair programming refers to two programmers working together at a single workstation with one writing the code and the other monitoring and navigating each line of code. Both the drivers and navigators can switch their roles from time to time.

Q21. While Building a Web Application, How Do You Consider SEO, Maintainability, UX, Performance, and Security?

Organisations that handle vital personal and other data have to focus on security while building a web application.  Small and medium-sized businesses need to focus on SEO and UX. Online publishers need to pay more attention to performance and SEO.

Q22. State the Difference Between SVG and Canvas

HTML5 comes with two graphical elements – Canvas and SVG to make the webpages more interactive and graphically attractive. The key differences between the two are:

SVG (Scalable Vector Graphics)	Canvas
The SVG is used to define vector-based graphics (vector image format).  The vector images can be stretched or compressed without losing quality.	Canvas is a raster-based format composed of pixels.
SVG provides better scalability thereby enabling good quality printing at all resolutions.	The canvas is not suitable for printing at high resolutions since it has poor scalability.
SVG can be modified through scripting and CSS.	Canvas can be modified only through the script.
The performance of SVG is better when dealing with fewer objects (<10k) or larger surfaces.	Canvas performs better when there is a smaller surface area or a larger number of objects (>10k).

Q23. What is Type Coercion in JavaScript?

Type coercion is the process of converting values from one type of data to another. For example, conversion of a number to a string or a string to a number.

Q24. What is the Difference Between <window.onload> and <onDocumentReady>?

Both the functions perform tasks once the page has been loaded in the browser but with a difference. 

• Window.onload: This is triggered when a web page has fully loaded which means the code is executed after the DOM and associated resources have loaded. DOM contains all HTML tags, like anchor tag, h1 tag, p tag, etc.
• onDocumentReady: The “onDocumentReady” method executes the code when the DOM has been loaded. It typically waits for HTML tags, anchor tags, etc., but not for images, videos, or other contents.

Q25. What are the Different Kinds of HTTP Requests Supported by RESTful Web Services?

The following HTTP requests are supported by the RESTful Web services:

• GET: It is used to retrieve data or resources from the server but only allows read-only access. No modifications are possible
• POST: It is used for creating a new resource.
• PUT: This is similar to POST but used for updating an existing resource
• DELETE: It is used to delete the resource from the server.
• TRACE: It validates the content along with the network during an HTTP request.

Top Web Development Interview Questions and Answers for Experienced

Here are some web developer interview questions for those with more experience:

Q26. What is the Best Way to Integrate Different Stylesheets into a Website?

The integration of different stylesheets into a website depends on the layout of the site and the way users interact with it. The best option is to use a single file called the styles.css since loading a single file is easier than loading multiple files. When you wish to change the style, you just need to open the styles.css file, scroll to the appropriate segment and modify the CSS. This sheet can be linked to your HTML.

Q27. How Do You Optimise the Loading Time of Your Web Application as a Web Developer?

Some techniques for reducing and optimising the load time of your web application are:

• Image Compression and Optimization – Although the use of images on your website will improve the appearance and quality of your pages. To avoid the problems associated with the use of larger images, compression and optimization should be used to improve the speed of the site. Small file sizes help in loading pages faster.
• Putting JavaScript and CSS in External Files – This action helps in maintaining the website easily.
• Reduce the Number of Redirects – A good way to improve the loading time of your website is to reduce the number of redirects.
• CSS and JavaScript Files Should be Loaded Asynchronously – Since multiple files are being loaded simultaneously, the loading time gets reduced thereby improving the performance of the website.
• Reduce the Size of HTML, CSS, and JavaScript Files – Eliminate unnecessary spaces, characters, comments, and other components to reduce the size of files. This will lead to faster loading of pages.

Q28. Define NPM (Node Package Manager)

The Node Package Manager or NPM is a default package manager for Node.js (JavaScript runtime environment). Included in every installation of Node.js, this command-line tool instals, updates, and uninstalls Node.js packages and modules required for Node applications or projects. A package includes all files for a module that can be added to a Node project when needed.

Q29. What are the Different Popup Boxes Available in JavaScript?

JavaScript uses pop-up boxes to display the notifications and messages for users. Some commonly used pop-ups are:

• Alert Box to display a warning message
• Confirm Boxes to obtain authorization or user permission.
• Prompt box to gather input for further use.

Q30. Explain the Term “Scope” in JavaScript and What are its Different Types

Scope refers to the extent to which the availability of variables or objects in an application can be managed. In JavaScript, there are two types of scope:

• Global Scope – A variable having global scope can be accessed from anywhere in the program.
• Local Scope – Variables with a local scope can be accessed from within the same function in which they are declared.

Q31. What are the Differences Between HTML and XHTML?

HTML or Hypertext Markup Language and XHTML or Extensible Hypertext Markup Languages are used to create web-based and Android applications. There are certain key differences between these two languages:

HTML	XHTML
HTML is a SGML (Standard Generalised Markup Language) application.	XHTML is an XML (Extensible Markup Language) application.
HTML is not case-sensitive.	It is case-sensitive. This means that every tag and attribute must be lowercase.
It is not necessary to mention quotes when using attributes.	It is necessary to mention quotes when using attributes.
.html and .htm are the filename extensions used.	.xhtml, .xht, and .xml are the filename extensions used.
It does not require writing the Doctype (document type) at the top.	It is very important to write the Doctype (document type) at the top of your file.

Q32. What is AJAX?

AJAX (Asynchronous JavaScript and XML) is a set of technologies used for developing web applications that are interactive and dynamic. AJAX is used by various web applications to send and receive data asynchronously from the server without hampering the display and performance of the existing data on the site. AJAX can be used to exchange information with a server and update portions of a webpage without having to reload the whole page.

Q33. What Does CDN (Content Delivery Network) Mean in jQuery?

CDN or Content Delivery Network refers to a geographically distributed group of servers that aid in delivering web content quickly. The use of these servers reduces the load times since the files are delivered at higher bandwidth from the servers located closest to the visitors of a website. Web programmers and developers can leverage the power of CDNs by hosting their jQuery libraries on them or using the ones already hosted on them.

Q34. Explain W3C (World Wide Consortium)

The World Wide Web Consortium was founded in 1994 for the improvement of the web. The consortium sets standards to ensure that all the stakeholders work in coordination with each other to grow the web. Some of the tasks performed by W3C include:

• Setting up and publishing web protocols
• Ensuring the development and growth of the web.
• Setting standards for web script applications and other dynamic content associated with the web.
• Ensuring that the set protocols are simple and extensible.

Q35. What are CSS Selectors? Can You Name a Few?

CSS Selectors are used for selecting HTML elements that need styling. Some commonly used CSS Selectors include:

• ID Selector 
• Class Selector
• Child Selector or Combinator

Q36. What are Pseudo-Classes?

Pseudo-classes are used to specify a special state of an HTML element. They can be used in conjunction with an existing CSS selector to add effects to elements, for example distinguishing between visited and unvisited links. Some commonly used pseudo-classes include:

• visited pseudo-class
• hover pseudo-class
• active pseudo-class
• focus pseudo-class 

Q37. Why are Media Queries Used in CSS?

Web developers can use media queries in CSS to create responsive web designs. This means that the appearance of a web page differs from one system to another based on the screen or the media being used. Media queries can be used to change the appearance or behavior of a site or app to match the browser features. The following can be changed in response to media queries

• Dimensions (width and height) of the viewport
• Dimensions (width and height) of the device
• Orientation
• Resolution

Q 38. What is Long Polling?

Long polling refers to a web application development method wherein information from the server is pushed quickly to the client by maintaining the connection formed between the two when the client first seeks information. This means that if the server receives a request from the client, it doesn’t close the connection immediately; the connection is only closed when the server sends the data back to the client or if there is a connection timeout.

Q39. What is the Difference Between Local Storage and Cookies?

Local Storage and Cookies differ on several counts:

Local Storage	Cookies
It generally stores large amounts of data on the client’s computer or browser as key-value pairs.	A cookie is a small text file that contains information about a website. When a user visits a website, the latter saves some information in the user’s system so that it can recognize the user and displays results quickly the next time.
Only the clients can access local storage. A server cannot use local storage unless it deliberately makes a request to the server via GET or POST.	Servers and clients are both able to read and write cookies.
Local storage does not have an expiration date and has to be removed manually.	Cookies have an expiry date.

Q40. What is the Purpose of Canvas in HTML?

Canvas (<canvas> tag) is an HTML element that allows the creation of graphics on a web page by using JavaScript. It allows dynamic control of graphics, images, and text on the webpages thereby making them interactive.

Q 41. What is the Purpose of Closures in JavaScript?

The closures are used to access the scope of an outer function from an inner function. A closure is created when a JavaScript function is created, and it allows web developers to control which variables are to be included in the scope of that function. JavaScript closures also allow control of which variables can be shared among siblings within the same function containing scope.

Q42. What is an Event Loop in Node JS?

Event loops are used for asynchronous programming in JavaScript. This ensures that all operations occur on a single thread, but an illusion of multithreading is created through the use of smart data structures. The event loop consists of different phases with specific tasks such that for the execution of an async function, the main thread sends it to another threat allowing the JavaScript engine to continue running its code.

Common Situational Web Developer Interview Questions

Employers not only test the technical knowledge of the applicants but also judge their ability to deal with different kinds of situations. The ability of a web developer to respond to different situations and resolve problems quickly is very important. Let us look at some common situational web developer interview questions that an employer may ask:

Q43. Explain JavaScript in Simple Terms

JavaScript is a programming language used for dynamic content such as animations, graphics, newsfeeds, slideshows, interactive forms, or anything on a web page that changes or moves even without the user hitting the refresh button on their screens. This language is also used for developing mobile apps, working on the backend of a website, and creating browser-based games.

Some other situational questions that the candidates may have to face include:

• Can you recall a time when you solved a problem that did not involve coding?
• How would your project managers and co-web developers describe you and your working style?
• How do you communicate your progress to the stakeholders and clients?
• How Would you describe web development to a person who is not well-versed with technology?
• Do you enjoy working with a team and What do you think are the factors that contribute to successful teamwork?
• How do you help your team members in improving their coding skills?

Common Behavioural Web Developer Interview Questions

Employers often ask web developer interview questions to judge your behaviour in dealing with problems and situations. While answering such questions, focus on how you dealt with a problem and what was the result of your actions. Some common questions asked by employers include:

Q44. Tell us About a Time When You Received Negative Feedback. How Did You Respond?

While answering such questions do emphasise that feedback is an essential part of the work process and that you welcome it. Rather than giving the example of a time when a client was unhappy because of poor work, talk about when a client was not pleased with an application even though it was developed as per an agreed-upon plan. Highlight how you dealt with the situation and introduced some changes or added features to satisfy the client. This will showcase your ability to adjust and respond to the client’s changing requirements.

Some more behavioural interview questions can be:

• Tell us about a project of which you are proud of. What worked out well in it?
• Tell us about a project that did not turn out well. What could have been done better or changed about it?
• Talk about a project which got stuck during the coding stage. How did you resolve the issue?
• Describe a time when your program did not run? What steps did you take to resolve the problem?
• Have you ever failed to meet a deadline? If yes, what went wrong and how did you rectify the situation?
• How do you deal with conflict among your team members?

Difference Between Software Developer and Web Developer

People new to the technology world often do not know the difference between software developer and web developer. While both a software engineer and a web developer study system relationships, programming, and databases, they use their skills in different ways and so have different career outlooks.

• Software engineers and web developers both study programming and learn to write codes but the former need to have formal education or a degree in computer science. In comparison, web developers may have an associate degree or have learned web development at bootcamps.
• Software engineers use their knowledge to create software products while web developers focus on building websites and other web applications.
• Software engineers generally work in technical departments with their work involving research and development, data science, and machine learning. In contrast, web developers may work in IT or marketing departments and need to have knowledge of JavaScript, CSS, and HTML to create visually appealing and user-friendly websites.
• Software engineers or developers generally work on long-term assignments while web developers may work on shorter and more varied projects. 

The demand for both software engineers and web developers is high and they continue to command good salaries.

Web Development MCQ Questions 

Q) What is the full form of CORS?

1. Centralized Online Registration System
2. Cross-Origin Resource Sharing
3. Centralized Online Resource Sharing
4. None of the above

Q) Which of these are pseudo-classes?

1. Focus
2. Visited
3. Hover
4. All of the above

Q) Which of the following is not a type of CSS Selector?

1. Active Selector
2. ID Selector
3. Class Selector
4. Child Selector

Q) Which of the following is not a type of pop-up box in JavaScript?

1. Prompt Box
2. Confirm Box
3. Inline Box
4. Alert Box

Q) In what ways can web developers reduce the loading time of their web applications?

1. By reducing the number of redirects
2. Through image compression and optimization
3. Minify HTML, CSS and JavaScript
4. All of the above

Q) The full form of NPM is?

1. Network Power Model
2. Network Programming and Management
3. Node Package Manager
4. None of the above

Q) What HTML5 element is used to attach multimedia files, such as video, audio, and photos?

1. Audio
2. Source
3. Video
4. Embed

Q) What HTML5 form element is used to generate an encryption key?

1. Keygen
2. Datalist
3. Output
4. Progress