JavaScript online skills assessment: Coding test to evaluate developers' data structures knowledge

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JavaScript (coding): data structures & data types test

Summary of the JavaScript (coding): data structures & data types test

This online JavaScript coding test evaluates a candidate’s ability to manipulate data structures and data types. This pre-employment assessment tests intermediate JavaScript programming skills. This test will help you identify and hire developers with essential JavaScript knowledge.

Covered skills

  • Data structures & data types

Use the JavaScript (coding): data structures & data types test to hire

Any developer who is expected to have practical experience using JavaScript. The difficulty level of these questions is geared to mid-level developers.


Programming skills


30 min





About the JavaScript (coding): data structures & data types test

JavaScript is a multi-paradigm coding language once focused solely on client-side web page behavior but is now embedded across desktop, mobile, and server applications. Recently, the language has been evolving very fast with the introduction of classes, generators, arrow functions, and many other features.

Working with and implementing data structures is crucial to the success of a developer. An effective data structure will enable you to effectively manage, organize, and represent your data. Data structures are often implemented as objects, so the ability to effectively work with objects and understand object-oriented programming is an important skill to have.

This coding test presents a real-life scenario to your candidates. They have 30 minutes to implement a data structure that meets the given requirements. Candidates can run the code against a selected number of test cases to see if they are on track. After submission, the code is automatically scored based on another set of test cases that also covers exceptions or corner cases. You will be able to play back how the code came about in the coding editor.

This test allows the candidate to showcase their knowledge about data structures in general, their ability to identify common problems, and their ability to solve those problems efficiently with JavaScript specific solutions.

We recommend combining this coding test with other tests evaluating the candidate's analytical and algorithmic thinking.

The test is made by a subject-matter expert

Kamil M.

Freelance programmer Kamil can’t be put in a box: from software development to systems administration to translations, he’s happiest doing a little bit of everything—particularly if it involves cybersecurity or data science.

A perfectionist at heart, Kamil credits his professional achievements to a belief that life-long learning and discovery are the key to reaching new levels.

Crafted with expert knowledge

TestGorilla’s tests are created by subject matter experts. We assess potential subject-matter experts based on their knowledge, ability, and reputation. Before being published, each test is peer-reviewed by another expert, then calibrated using hundreds of test takers with relevant experience in the subject. Our feedback mechanisms and unique algorithms allow our subject-matter experts to constantly improve their tests.

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Review from G2

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Our screening tests identify the best candidates and make your hiring decisions faster, easier, and bias-free.

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The JavaScript (coding): data structures & data types test will be included in a PDF report along with the other tests from your assessment. You can easily download and share this report with colleagues and candidates.

JavaScript_data_structures and data types test

What is a JavaScript online test? How will it help you?

An online JavaScript test is a pre-employment skills assessment that helps you evaluate your candidates’ expertise in developing incredible JavaScript applications for your business. This JavaScript test makes assessing multiple skills easier.

Industry experts have crafted and peer-reviewed our JavaScript online test to help you find the best mid-level JavaScript developer for your team. Whether you’re hiring internally, looking to fill a vacancy with a freelance programmer, or searching for full-time JavaScript developers, this JavaScript online test will help you evaluate all the skills your role demands.

JavaScript coding skills are crucial for your organization if you want to use one of the most popular programming languages to build applications.

And given that JavaScript is used in both front- and back-end development, your team can greatly benefit from JavaScript skills to build server applications, games, web pages, and web applications as popular as Netflix, Candy Crush, and LinkedIn.

However, you may have found it difficult to find applicants who have the full range of JavaScript skills you require. For example, your candidates may lack communication skills, empathy, or the ability to collaborate with others.

You may experience some difficulty agreeing with other recruiters in your department about which applicant to hire or struggle with a lack of talent in your candidate pool. If you’re a non-technical recruiter, it may also be the case that you don’t have any understanding of JavaScript. So how can you best assess a mid-level JavaScript developer?

Use this JavaScript online test when you have sourced promising programmers, and you’ll instantly see the benefits. Our test will automatically tell you which candidates are the best of the bunch. It will ensure that even as a recruiter without a grasp of JavaScript, you can make the most pragmatic hiring decision based on reliable statistical data.

JavaScript_data_structures and data types test

Evaluate 4 critical JavaScript data structure skills with this test

Our JavaScript online test makes it simple to assess all the technical JavaScript data structure skills related to your open role. Find out if your applicants have the following vital skills by using our JavaScript skills test:

Data structure implementation skills: Your new hire needs to know how to properly implement data structures to successfully develop applications for your organization. Find out how thoroughly your applicants understand linked lists, queues, stacks, and hash tables in JavaScript.

Data management skills: Use our JavaScript online test to evaluate your candidates’ JavaScript data management skills, whether they’ll be working with large databases and significant amounts of data or optimizing data structures in your applications to keep them clean and efficient.

Object-oriented programming knowledge: This JavaScript online test will reveal whether your candidates understand object-oriented programming in JavaScript. Discover if your potential hires know why blueprints and instances are important and how they relate to object-oriented programming in JavaScript.

Ability to solve data structure problems within a time limit: Knowing how to solve data structure challenges in JavaScript within a time limit is a critical skill that can help developers meet deadlines and code more efficient applications. Use the JavaScript skills test to assess how quickly and effectively your applicants can handle such problems.

JavaScript_data_structures and data types test

Select this JavaScript skills test to evaluate intermediate-level developers effectively

The JavaScript skills test makes hiring effortless in many other ways. Here are some more benefits of using this online test when you’ve sourced candidates:

Hire with confidence even if you lack technical skills: If you’re a non-technical recruiter, you likely find it challenging to determine whether your applicants have knowledge of JavaScript data structures and data types if you don’t have much programming knowledge yourself.

Let our subject-matter experts remove the stress from hiring. Use this JavaScript skills test to evaluate your applicants’ skills with our experts’ knowledge on your side to support your hiring choices.

Prioritize objectivity and widen your diversity with a bigger talent pool: By measuring candidates’ skills objectively, you can ensure your talent pool is diverse and increase the diversity of your team of JavaScript developers. Use this JavaScript skills test to prioritize objectivity, eliminate unconscious bias, and make discerning hiring decisions that will enhance your productivity long term.

Assess related skills in interviews using the JavaScript online test as a guide: You can also use this JavaScript data structures test to build better interview question lists. Consult your applicants’ JavaScript online test results before inviting them to interviews. Then, build your JavaScript data structure interview questions and follow-up questions using the knowledge you gained from your applicants’ results.

This JavaScript online test is just one of the 238 reliable tests we offer. These tests are used by 5,800 companies, including Technicolor and Oracle.

Are you curious about why so many businesses are switching from resume screening to TestGorilla? Sign up for a free account, and use our JavaScript test to recruit experts for your team.


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