The Top 10 Programming Languages Ranked By Starting Salary, & 70+ Sites to Learn Them for Free

Knoji reviews products and up-and-coming brands we think you'll love. In certain cases, we may receive a commission from brands mentioned in our guides. Learn more.

Aspiring developer? Get a jump start on your peers. Here's our list of the highest-paying programming languages to learn, and where you can learn them for free online.

Entering the job market for the first time or changing careers can be a daunting task. The job landscape has changed drastically in the last several decades, and you may be wondering what the most lucrative job skills are for the modern career hunter. The secret, it seems, is in tech, where computer programmers and developers are not only in high demand, but are also pulling in some seriously superb salaries.

In fact, according to the Bureau of Labor Statistics, software developers have a bright future ahead with a projected employment growth of 31 percent for app developers and 24 percent for general software developers by the year 2026. As a developer, you can anticipate a fantastic financial future - the average median salary for a developer surpasses six figures at $103,560 annually.

There are plenty of schools where you can learn various coding languages and get set on the path towards a job in software development. However, many of them come with a pretty substantial price tag, often surpassing $10,000 for one bootcamp. With many bootcamps, you’ll also need to be able to attend classes full-time which means you can’t work while you complete the course.

But, as computer programmer and author Ellen Ullman notes, “Computer programming has always been a self-taught, maverick occupation.” And, there are plenty of places out there where you can learn coding languages at your own pace and completely free of charge. With some hard work and a little investment of your time, you could set yourself up for an incredibly lucrative career without going into massive debt to get there.

That’s why we’ve put together this list of high-paying programming languages and where you can learn them for free online. Here’s what you’ll get in this guide:

  • A list of the top 10 programming languages aspiring developers should learn.
  • A ranking of those programs by entry level salary. Salaries are based on data from PayScale.
  • 70+ free online coding courses to learn each of these languages.

The top 10 highest-paying programming languages to learn


Entry Level iOS Developer Salary: $75,760

Swift is a programming language invented by Apple for building programs on iOS, macOS, watchOS, and tvOS. It was released in 2014 and is currently on its fourth version. One of the main advantages of Swift is that it uses much cleaner syntax than other languages, making writing code significantly easier as it more closely resembles the English language. 

The code itself is safe by design, but also runs incredibly efficiently. You can find the code open source on where developers across the globe are constantly upgrading and developing new applications for Swift.

By learning Swift, you’ll be able to apply for jobs as an entry-level iOS developer, which not only pays well, but is also an especially highly sought-after skill. Check out these websites where you can learn Swift for free online:

  • Again, since the code is open source, all of it is available for free on the Swift website.
  • Swift Playgrounds. This free app iPad from Apple teaches you Swift by having you build interactive playgrounds. You can even connect to Bluetooth and use the app to control robots, drones, and other hardware accessories.
  • Flatiron School. Offers a free 125+ hour course where you can learn Swift and connect with others online who are doing the same.
  • Udemy Swift Language Course. Check out this YouTube playlist from Udemy with 38 short videos that teach you the basics of Swift.
  • Bloc’s Learn Swift. This program teaches you Swift by having you build a 2D Tetris-like puzzle game for iOS.
  • Developing iOS 10 Apps with Swift. This course from Stanford University is available on iTunes and is great folks who learn better from classroom-style lectures.
  • Hacking With Swift. Offers free tutorials and 39 different projects to help you learn Swift in a hands-on way.
  • Code With Chris. Learn Swift through 14 tutorials, plus test out your knowledge with three challenges.
  • Udacity. Offers two free courses, Swift for Beginners and Intro to iOS App Development with Swift, both of which are a great setup for their nanodegree program in software development.
  • Take their free Intro to Coding with Swift, a great tutorial for beginners.  


Entry Level Developer with Python Skills Salary: $69,603

Python was first developed in 1994, and has remained very popular since then. It’s a general purpose language that can be used for a number of different applications and is especially useful for web design. 

Users often find that it’s a great beginner language as it’s easy to read and has fairly clean syntax. Since it’s been around so long and is open source, there’s also a vast library of open software and Python packages that you can use while building your own sites and programs.

Python is one of the most popular programming languages, and in fact, it only appears to be growing in popularity despite how long it’s been around. In addition to being a great skill for developers, it’s also a great language to know as a data scientist, also a highly lucrative field. You can learn it for free on these sites:

  • You can learn Python for free on this site, with a particular focus on its applications for data scientists.
  • Codecademy. Offers a free intro course on Python which is a great primer for their 10-week intensive course.
  • edX. This course on Python is presented for free from scholars at MIT.
  • Google for Education. A free course on Python from Google for folks with some coding experience. Learn through video lectures and hands-on exercises.
  • Udacity. Offers a free course on Programming Foundations for Python. This class focuses on object-oriented programming and is a great setup for their Full-Stack Developer nanodegree.
  • SoloLearn. Has both an app and a web-based option for learning Python that includes 92 lessons and 275 quizzes. Use the app to collect points and compete with other users.
  • Snakify. Teaches Python 3 through 11 lessons and 100+ coding problems. Students also learn the basics of HTML, CSS, and JavaScript as part of their Python training.


Entry Level Developer with C++ Skills Salary: $67,093

C++ is another useful general purpose language that has a history reaching all the way back to 1979. While it is not inherently a safe language — the C++ website recommends that people really know what they’re doing to use it — it is remarkably fast. 

As it is both an open language and one of the most commonly used worldwide, it translates easily to many different platforms with little to no changes.

Folks with knowledge of C++ can find work as software developers and in IT positions. Learn C++ on these sites for free:

  • Learn-C++. Offers a free interactive tutorial to teach you the basics and some advanced principles of C++.
  • Learn C++. It has the same name as the last entry, but this is a totally different tutorial. Learn C++ through 18 detailed chapters.
  • SoloLearn. Like their Python app, users can download an app or learn from their web browser. This interactive program is great for beginners, contains 80 lessons and 324 quizzes, plus has challenges where you can earn points and compete against other users.
  • Udemy. Their C++ Tutorial for Complete Beginners has over 18 hours of video divided into 82 lectures. 
  • edX. Microsoft offers a free Introduction to C++ on edX. The course is self-paced and takes around four weeks to complete with three to five hours per week effort. You can get a certificate upon completion of the course for $99 which can help with your job search.
  • Google. Has a free C++ class that covers the main things you need to know about C++ and helps you learn by completing two sample problem sets.
  • C++ Institute. Offers a free course on C++ that teaches you the basics of the programming language and touches on object-oriented programming. Take a weekly hour-long assessment after each chapter to test your knowledge.


Entry Level Developer with Java Skills Salary: $66,417

Java has been around since 1995 and remains incredibly popular today. It’s relatively simple to learn and its main benefit is that it is platform-independent, meaning it can be moved between computers running on different operating systems. 

Their motto is “write once, run anywhere,” (WORA), an advantage that makes knowing Java an especially useful skill. Java is currently the number one platform for development in the cloud which is important to note because cloud engineers and developers can earn even higher salaries than regular software developers. 

It was also named the most popular coding language by and currently ranks first on the TIOBE Index for most popular programming languages..

Knowing Java will make you quite versatile, especially since it can run across platforms. Here are some places you can learn Java for free online:

  • LearnJava. This interactive tutorial is great for people of all skill levels and lets you implement lessons with their hands-on, in-browser coding program.
  • Udemy. Offers a Java Tutorial for Complete Beginners including 16 hours of video lectures. You can get a certificate upon completion of the course.
  • edX. Microsoft also offers a free Learn to Program in Java course. It takes around four weeks to complete with six to ten hours of effort per week, and you can purchase a certificate upon completion for $99.
  • SoloLearn. Just like their other programs, you can learn online or in-app. This Java course has 65 lessons, 140 quizzes, and allows you to earn points and compete with other users.
  • Java World. Check out their free Java 101 tutorials to learn the basics of Java.
  • Tutorials Point. Try their Java Tutorial to learn Java basics, object-oriented Java programming, and even dive into advanced topics.
  • IBM. Offers an Intro to Java course with 12 hours of video lectures broken up into 23 units. Take quizzes and do programming challenges to test your new skills.


Entry Level Developer with Perl Skills Salary: $65,430

Perl was initially developed in 1987 and is currently on its fifth version. It’s one of the most popular coding languages used for web applications. One of the biggest advantages of Perl is that it’s a complete language, meaning it implements various pieces of several different languages into one easy-to-use, comprehensive programming language. 

This means that you can generally accomplish most tasks using only Perl, rather than swapping between languages, all of which you’d need to learn. 

Because it’s a complete language, it’s definitely a useful skill to have, but it should be noted that Perl has declined in popularity in recent years. Still, Perl developers can make a great salary and should be able to find work. Learn Perl for free on these sites:

  • Learn-Perl. Another free interactive tutorial from the Learn series which teaches you the basics and lets you practice with their in-browser coding program.
  • Beginning Perl. This free book series is available through the Perl website and has 14 chapters to take you from beginner to Perl coder.
  • Tutorials Point. Offers a free course on Perl. Students are assumed to have a basic knowledge of C programming and Unix Shell to take this course.
  • Perl Maven. Has a free tutorial, ebook, and video series on learning Perl. The tutorial includes recommendations for activities that will help you better learn Perl.
  • Guru 99. Check out their free tutorial that will walk you through downloading Perl and learning the basics to get you started.
  • Quick Code. Offers a free course on Perl that teaches you the main concepts.


Entry Level Developer with C# Skills Salary: $62,032

C# was developed by Microsoft in 2000 and is a general-purpose, object-oriented language. It’s typically used for backend programming and automation in Windows. Because it’s fairly close to Java, it’s a great language to learn alongside or in addition to Java, making you much more hire-able. 

One of the greatest advantages of C# is its safety — because it’s stored on your server in a binary, hackers won’t automatically have access to your source code in the event of a breach.

Because C# is typically used for backend development, and because backend developers tend to out-earn their front-end counterparts, it’s definitely a lucrative language to learn. Check out these sites to learn C# for free:

  • LearnCS. You guessed it! This program also has a C# course complete with their interactive coding program and useful tutorials on the basics of C#.
  • Code Easy. Offers free beginner and intermediate courses on C#. It employs adventure storytelling and interactive tasks to make learning the language fun.
  • SoloLearn. You can use their useful program on the web or in-app to learn C# and earn points to compete against other users and test your skills.
  • edX. Microsoft also offers a free C# tutorial which takes around three weeks at three to five hours of effort per week to complete. Get a certificate upon completion for $99.
  • Tutorials Teacher. Learn everything from the basics to advanced skills in C# with their tutorial containing 58 separate chapters on various topics.
  • C# Station. Beginner and intermediate coders can learn the essentials of C# with this volunteer-built tutorial made up of 23 useful lessons.
  • C# Beginners Tutorials by The New Boston. Although The New Boston is no longer active online, you can find their series of C# beginner video lectures here on Cosmo Learning.


Entry Level Developer with Ruby Skills: $60,157

Ruby first appeared in 1995 and has gained popularity ever since. One of the main reasons for its popularity is that it’s quick to write, with some statistics suggesting it’s up to 30 to 40 percent faster to develop projects with Ruby than with other languages. It’s object-oriented and because of its ease of use, it’s much simpler to avoid bugs and create high-quality code. Ruby is a general purpose language, but it most commonly used for web applications.

Most importantly, Ruby is the programming language used in Ruby on Rails, the web application framework that is implemented in Ruby. Ruby on Rails is used frequently

Although many coders have joked that Ruby is dead, it still ranks 15th of all the most popular coding languages on the TIOBE index and is a great skill to have due to its speediness. Here are some sites where you can learn Ruby for free:

  • LearnRuby. Another great tutorial from the Learn series, get the basics of Ruby and hand-on experience with this course.
  • Codecademy. Take their free tutorial on Ruby which ends with an interactive final project.
  • Ruby Monk. Offers four free interactive tutorials that can help take you from beginner to advanced. Ruby creator Yukihiro Matsumoto even uses these tutorials himself to get a better grasp on the language!
  • Bloc. Their free Ruby Warrior game is a fun, interactive way to learn the basics of code in a gamified format.
  • Flatiron School. Offers a free 30-hour online Intro to Ruby course for beginners. Students learn the basics and ultimately put them to the test by building their own fully-executable game of Tic-Tac-Toe using Ruby.
  • Ruby on Rails Tutorial. This book is available for free online and is a great resource for folks who learn best through reading. It’s got 14 comprehensive chapters broken down by subject to help you get the basics.
  • CoderByte. Try their free Learn Ruby in One Week program. Students learn the essentials of Ruby and complete several fun interactive challenges.


Entry Level Programmer Analyst with R Skills Salary: $58,973

R is a language that’s been around since 1993. Although R is a general purpose language, it is most often used for data analysis, simulation, graphics, and statistical modeling. R is not the simplest language to use and because of its typical applications, it’s less suited for developers than it is for folks who are interested in going into data science and other analytical fields. It is, however, a cross-platform language and interacts well with other statistical analysis tools.

Because it’s a data science-driven language, it’s a great skill to have if you’re on that track. And, data scientists tend to earn quite a bit more than developers, starting at $87,629 annually. Here are some places where you can learn R for free:

  • Data Camp. Offers a free four-hour introductory course in R. It’s an especially good place to start if you want to pursue one of Data Camp’s R programming or data science tracks.
  • edX. Harvard Extension School developed Data Science: R Basics course which you can take free on edX. It uses real-world data sets to help you learn R by problem solving. The course takes four weeks of two to four hours of effort each to complete, and you can get a verified certificate at the end for $49.
  • swirl. Provides instructions on installing R. You can then install one of their many courses on R from their course repository.
  • Data Mentor. Offers a free tutorial on installing and using R, particularly with a data analysis focus.
  • Udemy. Check out their R Basics - R Programming Introduction for free. The course has four hours of on-demand video, and you can receive a certificate upon completion.
  • R for Beginners. This guide is available as free PDF through Berkeley. It’s pretty dense, so it’s probably best for folks who learn best by reading.
  • Cookbook for R. A step-by-step online guide that teaches you the essentials of R. Much of the code mentioned into the tutorial can be plugged into an R command window if you want to see how they actually work.


Entry Level Developer with JavaScript Skills: $55,378

JavaScript first appeared in 1995 and was originally developed for NetScape Navigator - remember that? It’s typically used in website design as a way to make your site more interactive and user-friendly, and is often deployed in conjunction with HTML and CSS. 

Because it operates on the client side, it allows sites to run much more quickly and reduces overload on servers. It’s incredibly versatile, and is popular in part because it can produce the same result on essentially all modern browsers.

Because it’s most often used with other languages, it’s a good idea to learn the basics of coding, especially HTML and CSS, before embarking on a career in JavaScript. However, these sites can help you learn the language for free:


Entry Level Developer with PHP Skills Salary: $50,260

PHP didn’t start out as a programming language, but grew that way organically as creator Rasmus Lerdorf continued to tinker with it and implement it on his own personal website - hence, the name Personal Homepage/Forms Interpreter (PHP/FI). 

PHP is a general purpose language but is generally used for server-side scripting, one crucial piece of backend developing. Its main advantage is its speed, which is why many people opt to use PHP as part of their backend programming.

Again, backend developers tend to outearn their front-end peers, so having knowledge of PHP could set you on a path for a well-paying backend position. Learn PHP for free on these websites:

  • LearnPHP. Check out the Learn series on PHP for an in-depth and interactive tutorial on the language.
  • Udemy. Offers a free Beginner PHP and MySQL Tutorial which is a great way to learn to develop web apps while learning two useful skills. The course contains over 10 hours of video lectures, and you’ll get a free certificate upon completion.
  • W3Schools. Check out their free tutorial on PHP 5. This course is interactive and contains lectures starting from the beginning up to more advanced subjects. You can purchase a certificate for $95 upon completion of the course.
  • SoloLearn. Like their other programs, you can study PHP online or through their app and complete challenges to open more new interactive levels as you unlock more achievements.
  • Code Course. Has 125 different video courses on PHP-related subjects.
  • Hacking with PHP. This site offers a 25 chapter tutorial that can introduce you to the basics of PHP and get you started on some more advanced subjects.
  • Home and Learn. Offers a free tutorial on PHP. Users should have a base knowledge of HTML before hopping into this particular program.

You could be on your way to a much more lucrative career in web, app, or software development in just a few short weeks. And, with this guide, you’ll be able to get that new career off the ground with almost no expenses upfront. So, what are you waiting for? Pick your language and get coding!

Want more useful guides like this to help you make - and save - money everyday? Be sure to keep up with the Knoji blog, and check out the Knoji homepage where we’ve answered thousands of questions about discounts from your favorite retailers.