Top 5 Functional Programming Languages in 2026

With functional programming languages, you can create more easily maintainable software. Functional programming uses functions as values, which allows you to reuse code more frequently. Through the process of functional programming, functions return a consistent output value after receiving an input value. Read on to learn more about the most popular functional programming languages to help you get started in the field.

What is a functional programming language?

Functional programming differs from object-oriented programming in that functional programming often uses immutable data, while object-oriented programming often uses mutable data. Mutable data means that the data structures can change, whereas immutable data cannot. 

The rise of big data and machine learning in recent years has made functional programming increasingly popular. 

Functional programming is great for performing analysis on large sets of data. It also allows for efficient debugging to quickly identify and correct errors. Additionally, you can use functional programming in artificial intelligence, complex math function models, and financial programs.

Top 5 functional programming languages to know 

According to data from Statista, these are the five most in-demand programming languages [1]. They all have functional programming capabilities.

JavaScript

JavaScript is a multi-paradigm language, meaning you can use it for object-oriented and functional programming. JavaScript is great for building dynamic, user-friendly websites. You can use JavaScript in a wide variety of applications and careers. This language is most common in web, front-end, and back-end development. However, mobile application and game development careers also utilize JavaScript programming skills.

Java

Java is also a multi-paradigm language that can be used for functional programming. It is useful for building software that can function in several operating environments. Its versatile features allow you to manage data processing and run statistical analyses.

Python

Python is a multi-paradigm language that can support functional programming. It is beginner-friendly, which is helpful if you’re new to programming, while also offering flexibility in terms of what you can do with it. You can use Python to perform tasks in many different disciplines. This includes web development, data science, cybersecurity, and more. 

TypeScript

TypeScript is a multi-paradigm language similar to JavaScript, offering additional features, such as type safety, function overloading, and interfaces to improve the development process. This makes TypeScript easier to use. Additionally, it can run in any environment where JavaScript runs, including different operating systems and browsers.

C#

This multi-paradigm language has features to support functional programming techniques. With C# programming as part of your skill set, you can create several applications, including web and game development and Windows applications. C# is similar to JavaScript and other C languages, so if you have previous experience in those languages, you will find commonalities when learning C#.

Additional functional programming languages to learn

Several other popular functional programming languages to consider learning include:

Scala

The name Scala is short for scalable language, and this language blends concepts from both object-oriented programming and functional programming. As its name implies, Scala offers excellent scalability, allowing it to grow to meet your programming demands. This is because Scala takes complementary features from both object-oriented and functional programming, allowing you to create large systems or basic scripts. 

Haskell

Haskell offers several beneficial features for functional programming, although it is a specialized language with a reputation for being challenging to learn. With Haskell, you can write efficient code with minimal errors. It works well with complex datasets—even those with inconsistencies—and integrates with other tools for your machine learning projects.

Erlang

Erlang is a reliable option for building large and scalable telecommunications, banking, gaming, and distributed systems applications. It is also suitable for systems where high availability is a requirement.

Elixir

Elixir is an easy-to-learn functional programming language that offers flexibility when working on different cloud platforms. You can use Elixir for software development to build applications, embedded systems, web APIs, and more. Companies that rely on programmers with Elixir programming skills include Pinterest, Adobe, and Discord.

Ways to learn functional programming languages

If you’re ready to learn how to code, you should consider what you want to accomplish with your programming skills. That might be a specific career path or a project you’d like to complete. With this in mind, you can narrow your options and choose the right language. 

You have several options for learning a new programming language. One option is through a boot camp. Boot camps are short-term but intensive programs to help you develop the skills employers seek. You can build a portfolio to demonstrate your skills and experience during a boot camp. You can find boot camps both online and in person, as well as part-time or full-time to accommodate your time constraints. Camps generally last anywhere from three to six months.

You can also find free resources online to learn different programming languages. This allows you to move through the material at your own pace without any financial commitment. However, with this option, you won’t have the same guidance and resources as with boot camps. Additionally, you will likely need to take multiple online courses to obtain the same level of information.

Get started with functional programming on Coursera

Functional programming languages are a key component of many businesses’ web and application strategies and are used to create new applications across various industries. Learn more about developing these skills on Coursera, where you can find several highly rated courses to help further advance your functional programming skills.

If you’re new to programming, the JavaScript for Beginners Specialization from UC Davis is an excellent introductory course to help you learn core programming structures and build skills through the progressive modules.

To learn the foundations of back-end coding and programming with C#, consider enrolling in the Microsoft Back-End Developer Professional Certificate. There, you'll apply object-oriented programming principles in the creation of modular, scalable solutions in C#, through coding projects.