Top 50 React JS Interview Questions

Top 50 React JS Interview Questions

The interview is one of the most important phases of the hiring process to assess the React JavaScript developer skills and attitude. A good interview is characterized by a good set of React technical interview questions along with a few personal assessment questions.

Let’s talk about the top 50 React JS coding interview questions and have a look at different aspects of a successful interview to hire the right React developer remote professional. 

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Overview of a ReactJS Developer Interview

Formulating a good interview for hiring a good ReactJS developer consists of many components to consider. The process of an interview, signs of a good interview, and the types of questions to be asked are a few most important aspects of an effective interview. Let’s explore these factors in detail.

React Interview Process

The React interview process starts once the resume screening and personal screening processes are completed successfully. The interview process starts with an appointment date of interview. The interview process may consist of one or more than one session as per the company HR policy.

Signs of Successful Interview to Hire React Coder

The signs of a successful interview to find React JS developers include numerous factors, a few of those signs are given below:

  • The confidence shown by the candidate
  • Positive facial impression and body language of the interviewers
  • Positive and enthusiastic comments given by the interviewers
  • Participative/interactive approach shown by the candidate even the answer was not satisfactory
  • If interviewers start talking about perks and the company environment
  • The duration of the interview increases than the expected time
  • Interviewers talk about how will you fulfill your React JS responsibilities in the company

What Interview Questions on React JS Should Be Asked?

In a professional interview to hire a React JS developer should be asked different types of questions that can help explore the skills, qualities, capabilities of the candidate. A good candidate with an attractive React JS CV should be asked questions in the following categories.

  • Technical category – This should include questions related to JavaScript, React JS, Redux, and web development
  • Professional category – In this section, the interviewer should ask questions regarding previous experience, achievement, disputes, attitude, innovative ideas, and other soft skills.
  • Personal category – This category should include questions related to interest, salary, perks, overloads, sincerity, thought pattern, expectations, and others.

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Top 50 React Redux Interview Questions

To make an interview session more effective and productive, include the following questions in it.

  1. What do you know about React?
  2. What features of ReactJS are putting it in high demand?
  3. How many components in ReactJS have you worked with?
  4. What is the difference between props and components in ReactJS?
  5. What do you know about the “State” in ReactJS?
  6. What is the major use of Redux on ReactJS apps?
  7. What do you know about “state management” in ReactJS?
  8. Why is it not recommended to update the state directly?
  9. How can you differentiate the event handling in ReactJS and HTML?
  10. What do you know about JSX?
  11. How does JSX help in preventing Injection attacks?
  12. Why are class components preferred over function components?
  13. What is a key prop?
  14. What are the benefits of using key props and when to use them?
  15. What do you understand by virtual DOM?
  16. How will you differentiate between DOM and virtual DOM?
  17. What is the working process of DOM in ReactJS?
  18. What do you know about higher-order components (HOC)?
  19. How many common types of HOC implementation are there in ReactJS?
  20. What is the process of creating HOC through render props?
  21. How can you add Bootstrap to ReactJS apps?
  22. Why is the boiler-plate ReactJS stack so popular?
  23. What is a Ref?
  24. Why avoid the use of inline ref callback in most cases?
  25. How can a “ref” be created?
  26. For what purpose the React-DOM package is used?
  27. What do you know about ReactDOMServer?
  28. Can you use Redux with any other JavaScript library?
  29. What do you know about the React DevTools?
  30. What is Flux used for?
  31. Can you name the core principles of Redux JS?
  32. How will you differentiate between Redux and Flux?
  33. What React function is commonly used to access the Redux store?
  34. What is a container in the React JS library?
  35. What is the difference between React container and component?
  36. What do you know about the Redux-Saga?
  37. How can you differentiate between Redux-Saga and Redux-thunk?
  38. What is a styled-component?
  39. What do you know about the use of the Relay framework in React JS?
  40. What is the main purpose of render hijacking through HOC in ReactJS?
  41. What is the React.memo function in React JS?
  42. How to use the setState function for preventing unnecessary updates?
  43. What is the importance of hooks in ReactJS development?
  44. How many rules are there for using the hooks?
  45. How do you elaborate on the benefits of React Router V4?
  46. What is the purpose of using error boundaries in ReactJS?
  47. What do you know about the constructor in the React JS library?
  48. What the NextJS framework is used for in ReactJS development?
  49. What is the purpose of dynamic import in the React JS?
  50. What is a suspense component?

How Can You Benefit from Our Professional Help?

Searching and hiring the right React JS developer is a professional task, which requires specialization and expertise. We offer one of the most professional-level React JS team recruiting services on how to find a great React developer that is the most suitable for your projects.

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On your behalf, we:

  • Search, resume screen, candidate screen, shortlist, fix interviews, conduct test, offer job, and onboard the ReactJS developers
  • Provide hassle-free and fully managed service
  • Build, augment, and manage your React development team
  • Offer remote web development infrastructure for developers
  • Provide access to a wide range of React JS developers

Contact us now to get a free consultation on the effective hiring of ReactJS developers and the advantages of working with the professional providers of ReactJS dedicated teams!

React Developers for Hire: How to Choose the Best Candidate?

React Developers for Hire: How to Choose the Best Candidate?

Being in great demand, it is very difficult to find the right React JS developer to play important JavaScript developer roles and responsibilities in a web development team. Due to the shortage of qualified React developers, the available candidates are so demanding. In such circumstances, choosing the right candidate is a tricky matter.

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Let’s have a deeper perspective on the difficulties many companies face, and the major telltale qualities of a ReactJS test candidate and a step-by-step procedure to hire the right React developer.

Major Difficulties in Hiring the Right ReactJS Developers

In a high paced market of web technologies, it is a very tedious job for the companies to find and hire ReactJS developer professionals suitable for filling the vacant positions. In every HR management phase for ReactJS developer, new challenges arise for the businesses. Let’s figure them out precisely:

difficulties to find react developer

  • Difficulties to find the desired skill – ReactJS is a comparatively new technology and demand is very high that poses new difficulties to find the right candidate with the right skill set.
  • Verifying the skills on resumes – In the given conditions, verifying the skills on a long and comprehensive React JS sample resume is a challenging task indeed.
  • Scarcity of active job seeker – The ratio of active job seeker developers with React JS certification is very low as compared to passive candidates, which are so demanding and companies are unable to live up to their expectations.
  • Relevant experience – The requirements of different projects are very unique so it is a big problem for companies to find a candidate with the exact relevant experience.
  • Hefty salaries – In a fiercely competitive environment, salaries have become a big problem for companies, especially for SMBs and startups.
  • Tech-talent retention – Retaining a hired ReactJS developer is also a big challenge for the companies.

Step-by-Step Procedure of Hiring a Certified React Programmer

What skills should a good candidate have? What question can be asked for recruiting person for React JS role? And many other similar types of questions are very commonplace stuff in the HR recruiting for React JS developers. Let’s address such questions in a step-by-step hiring process for a great ReactJS developer.

hiring react programmer procedure

Step #1. Researching

Researching or resourcing is the most fundamental process to start with for finding the right React programmer qualifications and skills. The major resources for searching candidates can be any one of the following:

  • Social media websites
  • Freelance websites
  • Online job portals
  • Newspapers and bulletins
  • Google searches

Step #2. Screening

In this step, you should filter the CVs of the candidates with the most relevant skills, experience, and qualifications. This process should be done carefully so that no relevant CV is dropped out. This can be done manually as well as through an automated software program.

Step #3. Candidate Shortlisting

In this step, a few introductory and React JS interview questions should be asked to the candidate for fixing a further technical test and interview. This is just an overview of the candidate and his/her skills to prepare for a full-fledged technical assessment.

Step #4. Technical Screening

This step is one of the most crucial one in terms of technical skills verification. This step can be divided into multiple sections such as a technical interview and a test. A technical test is very useful in JavaScript candidate code assessment through a scenario-based or a case-based test. This step may involve two or more sessions.

Step #5. Personal Interview

After the completion of the technical assessment, it is time for a personal interview to discuss the soft skills, salaries, and other matters related to the job, company, and personal interests. Highlights of the previous experience such as achievements, disputes, or other matters are discussed in this step.

Step #5. Job Offer

In the light of the scores of the technical and personal screenings, a final job offer is sent to the candidate for his/her final acceptance.

Step #6. Contacting

Once the job offer has been accepted by the candidate. The final contract with additional rules and regulations of the company and other governmental authorities are included in the offer to get it signed by the candidate.

Step #7. Onboarding

Finally, the candidate has to join the company with a joining letter and the HR manager should take him/her for company orientation and introduce the entire team.

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What Skills to Look for in Candidate to Recruit for React JS Role?

Selecting the right candidate is a tricky matter and needs professional expertise. To make sure that you are hiring the right ReactJS candidate, check the following telltale signs.

Technical Skills:

  • Candidates have in-depth knowledge of basic web development languages like HTML, CSS, JavaScript, and ReactJS platforms like ReactJS, jQuery, Immutable, Redux, etc.
  • Expertise in all aspects of ReactJS library such as DOM, React elements, JSX, ES6, data binding, etc.
  • Extensive knowledge of different tools like Babel, webpack, npm, typescript, GitHub

Soft Skills:

  • Great understanding and listening skills
  • Creative and solution-oriented thinking
  • Great interpersonal and written communication skills
  • Commitment, sincerity, time management, team player


  • Substantial experience in working with ReactJS and other JavaScript environments
  • At least a university degree in computer science or software engineering
  • Specialization in ReactJS platform through certification
  • Prior experience in the relevant fields that match your job requirements  

How Can We Help You Form Strong ReactJS Development Teams?

We are a team of expert recruiters from Ukraine that offer fully managed and highly professional-grade recruiting services to our valued customers. Powered by automated tools and state-of-the-art robust infrastructure and experienced management, we can use all available resources for hiring a few of the best React JS developers in the market.

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We accomplish all steps of recruiting one of the top tech-talents on your behalf and provide the most desirable outcome of those processes. Our professional-level services offer you:

  • Highly skilled, experienced, qualified ReactJS developers
  • Access to a very large tech-talent pool in Ukraine
  • Highly robust and reliable infrastructure for remote work
  • Fully dedicated teams at very competitive prices without any hidden charges
  • Full control over the React JS development team
  • Flexibility to scale your team at any time
  • Faster hiring process
  • Ideal geographical location

If you are looking for great ReactJS developers for hire, ask for a quote to help you in building your development team with highly talented ReactJS developers!

How to Find a Great React Developer: the Ultimate Guide

How to Find a Great React Developer: The Ultimate Guide 

The demand for ReactJS developers is consistently increasing with the increasing popularity of the ReactJS library in the marketplace. According to the StackOverflow Survey 2020, React JS is the second most popular framework after jQuery in the marketplace. Numerous employers use different options to find JavaScript developers with ReactJS expertise for their respective projects.

Let’s talk about the popularity and top skills in a React developer resume to hire remote ReactJS developer and also the best ways to find great ReactJS developers.

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Why Are React Developers for Hire in Great Demand?

The demand for web developers, especially React JS developers is huge across the globe. This huge demand is driven by numerous reasons and factors as listed below:

  • ReactJS is based on JavaScript technology, which is the leader in the web development domain
  • React JS library is powered by Facebook, which is a big name in the technology sphere
  • React JS has a huge library and a wide range of tools and custom apps
  • Supports virtual DOM and two-way data binding performance and security
  • Offers faster web development with an innovative approach
  • It is an open-source JavaScript library free to use
  • Options for creating great and innovative solutions

What Capabilities Should You Check to Hire ReactJS Developers?

It is a very challenging task to find React.JS contract remote for hiring a developer with the desired skills and qualities. A few major capabilities to hire a React JS developer for React.JS development services are listed below:

  • Command over the basic web development languages like HTML, JavaScript, and CSS3
  • Experience in Flexbox, box model, Semantic tags, and responsive web principles
  • Expertise in React JS development and its allied tools
  • Command over virtual DOM, JSX, React.createElement() API
  • Experience in Node JS and Node Package Management NPM
  • Experience in working with Redux for state management
  • Should have working experience with Enzyme, Webpack, Jest
  • Knowledge of Git, Sentry for Real, component lifecycle
  • Strong interpersonal communication skills and a solution-oriented approach
  • Command over debugging, troubleshooting, testing, and performance checking

What Can React Developers Contribute to the Success of Projects?

React developers for hire contribute significantly to developing great quality, timely delivery, and innovative solutions to the project. All those factors make a project successful. This is the reason that businesses either hire ReactJS development company or choose the services of React developer recruiting to make their projects big successes.

The main contributions made by a professional React.js developer include:

  • A better translation of customer requirements into a web solution
  • Faster completion of the project by using reusable React components
  • Efficient use of huge ReactJS library functions
  • Choosing the right process for the right solution in the ReactJS environment
  • The effective use of cutting-edge web development technologies and tools
  • Develops highly responsive, interactive, and secure web apps

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How to Find a Great React Developer in the Marketplace?

You can find a ReactJS developer through multiple ways in the local as well as in the international market for ReactJS developers. A few very important ones are mentioned below.

Freelance Boards

Freelance boards are online websites and applications that offer the profiles of numerous ReactJS web developers and other human resources. The role of those freelance boards is just as a facilitator to provide a platform, where the employers and job seekers meet. They rarely guarantee the quality, success rate, or reliability.


  • Offers very low prices
  • A large number of developers
  • Charge a short fee or commission


  • The least reliable source of hiring
  • Difficult to find the right talent for the desired job
  • Need expertise in the hiring process to hire a developer
  • No control over the availability of developers for your projects
  • Many types of strict user policies and rules to use the service

Social Media Forums

Social media forums have turned into great platforms for hiring different types of developers like ReactJS developers and others. The major social media forums such as LinkedIn, Facebook, and others. According to a study, LinkedIn is the leading social media platform for hiring with over 75% of the people using this platform for their job changes. They are becoming a very attractive platform due to numerous benefits as mentioned below.


  • A large number of developers available for hire
  • Access to a huge ratio of passive candidates along with active candidates
  • The quality, skills, and experience are verified by their colleagues, past employers, and other professionals
  • A proper recommendation system provides better insight into the capabilities of the developer
  • Easy and free to use those platforms for individuals and recruiters


  • Chances of fake recruiters and profiles
  • Hiring passive candidates are very costly
  • The candidate privacy is at stake
  • Job retention for companies become a challenge

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Recruitment Agencies

Using the services of a React JS outsourcing vendor or a recruiting agency is another important way of hiring a React JS developer. In this method, employers seek the services of recruitment agencies, which search for the desired developers from their databases and other local resources.


  • A much reliable source of hiring
  • Professional recruiting service
  • Fully managed hiring service
  • Full control over the hired developers


  • A bit costly solution
  • The hiring process costs money
  • Access to a limited number of developers
  • Hefty fees of hiring developers
  • Longer process of hiring

Outstaffing Companies

Outstaffing is a very popular model of ReactJS developer hiring, in which a hiring service provider hires a dedicated developer or a team of developers to work for a company remotely. The team is fully managed and delegates full control to the employer.

why work with react js outsourcing vendor


  • Fully dedicated developers
  • Fully managed service
  • Full control over tech-talent
  • Competitive prices
  • Highly flexible and reliable method of hiring


  • Diversely located teams
  • Challenges of remote team management

What Is the Best Option to Hire ReactJS Team?

Hiring the Ukrainian contractors front end React team through outstaffing is the best of all the above-mentioned options. Outstaffing offers cost-efficiency, reliability, flexibility, and control over the team, and hiring from Ukraine offers you numerous additional benefits.

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A few of the benefits of hiring React JS team through outstaffing in Ukraine include:

  • Skilled, qualified, and experienced developers
  • Offers guaranteed quality and reliability of service
  • The cost of hiring is very reasonable
  • Access to a large pool of developers
  • Ideal geographical location

If you are looking for hiring great ReactJS developers, get in touch with us to explore more suitable options for choosing the great developers for your needs!