12 JavaScript Code Challenges for Beginners

12 JavaScript Code Challenges for Beginners

Online courses are a great place to learn the foundations of code. But it’s when you put things into practice that you cement the concepts into your brain.

Figuring out how to solve problems and conquer coding challenges can be truly rewarding (and fun!). Stephanie, a Software Developer from Baltimore, shares why practice (including code challenges) is key to mastering a programming language:

“Codecademy is a great starting point for learning different programming languages and introducing concepts, but there’s only so much you can cover in a course. A good chunk of mastering a language is learning through experience.”

In this article, we’ll share 12 short beginner JavaScript code challenges that you can tackle. Try selecting one each day and see how you do. We’ll also share how you can continue challenging yourself and your JavaScript skills after completing our suggested list.

Top 10 JavaScript code challenges for beginners

Each of these challenges is suitable for beginners, but you may find that having a base-level knowledge of JavaScript is helpful. Or, if you have a little bit of experience, you might benefit from refreshing your knowledge with our introductory course on JavaScript.

While we don’t specify here, you can use whatever coding environment suits you best. You can use what you’re comfortable with on your local machine, or you can use the environments you’re familiar with in online JavaScript courses. Don’t forget that Google can also help if you find yourself stuck on a coding problem, but try to see if you can create a solution before heading to the search engine.

1. Print all even numbers from 0 – 10

Try to make the solution to this problem as efficiently as possible. Consider using loops that would allow you to type the fewest characters/commands. While you could simply print the even numbers, get creative and see how you could output them in a way that would work up to 10 or even up to 10,000 with little extra effort.

2. Print a table containing multiplication tables

Let’s start with the tables that many of us had to memorize in school. Can you print a table that contains all the answers to the multiplication tables from 1 through 10?

Like Challenge #1, can you create an efficient solution that you could easily expand should you need the 12 times table?

3. Create a length converter function

Creating a function is a skill that’ll be useful in many settings, and as you progress, you’ll be working on much more complicated functions than this one. But a function that converts units of measure can be pretty handy in multiple professions and industries.

Let’s start with a conversion from kilometers to miles. The function should include the input in kilometers and return the answer in miles.

4. Calculate the sum of numbers within an array

You can create your own array of numbers but consider trying this problem with a few different sets to verify your solution. Have one array with negative and positive numbers and another with integers and decimals.

You could also try using arrays of different lengths. If you’re feeling comfortable with this, try the slightly more challenging bonus challenge below.

Bonus intermediate challenge: Create a function that can return the sum of a particular column or row number in a table.

5. Create a function that reverses an array

This challenge is particularly helpful if you’re planning to become a Data Scientist. Manipulating data is a significant part of the role, and building the foundations now will help you later down the road when you’re working with large databases.

Start small here and work your way up. Begin with an array of 5 numbers, and then try your program with a larger array to verify its success.

6. Sort an array from lowest to highest

You could create a function for this solution as well, but be sure to try your program with varying lengths and types of arrays. Try one with all integers, another with negative numbers, and another with decimals.

7. Create a function that filters out negative numbers

In this challenge, you’ll have a function that takes an array as an input and returns an array. But if all goes according to plan, it’ll remove the negative numbers. This is another example of a task that’ll be useful when combing through data and looking for clever ways to eliminate “bad data.”

8. Remove the spaces found in a string

Yet another way to clean up data is to remove any errors or unnecessary spaces. This function will take in a string and then return it with all spaces removed. Think about if you were tasked with cleaning up customer data at your job. You could scale this function to clean up specific fields of data, such as zip codes.

9. Return a Boolean if a number is divisible by 10

Here, you’ll create a function that’ll give you a “true” or “false” Boolean as its output. The inputted number should only return a “true” if it’s divisible by 10. Otherwise, your program should return a “false” answer.

10. Return the number of vowels in a string

Create a function that’ll return an integer of the number of vowels found in a string. This is a great way to practice determining the features of a dataset. If you use JavaScript later in your career, you’ll be well-prepared to determine what datasets (or just strings) consist of. If you feel like an extra challenge, consider returning the number of characters.

11. Create a function that finds the maximum number in an array

In this challenge, you’ll write a function that takes an array of numbers as an input and returns the largest number in that array. Test your function with various arrays, including arrays with negative numbers, decimals, and all positive integers.

12. Check if a string is a palindrome

A palindrome is a word, phrase, number, or other sequences of characters that reads the same forward and backward (like the words “kayak,” “mom,” “radar,” and “refer”). Create a function that takes a string as input and returns a Boolean indicating whether the string is a palindrome. Test your function with different strings to ensure it works correctly.

Brush up on your JavaScript with courses and challenges

If you enjoyed putting your JavaScript skills to the test with these challenges, then consider signing up for more by downloading the Codecademy Go app. Participating in our daily or weekly challenges is an excellent way to keep your skills fresh and continue learning to solve problems.

If you wish to go a little deeper with your learning or explore more complex problems and coding challenges, consider taking an intermediate-level course. You can learn more and level up your skills to prepare for your future career with courses and Skill Paths like Create an Advanced Web App with React and Reduct or Create a Back-End App with JavaScript. So what are you waiting for? Get started today!

This blog was originally published in August 2021 and has been updated to include additional JavaScript challenges for beginners.