Here, we curate and share some of the best coding challenge websites that you can use to sharpen your programming skills. Whether you're a beginner or a seasoned professional, there's something here for everyone.
Coding challenge websites are a great way to practice coding, learn new algorithms, and prepare for coding interviews. They typically provide a series of problems that you solve by writing code. The problems range in difficulty from easy (suitable for beginners) to hard (for experienced programmers). Some sites even offer competitions where you can test your skills against other coders.
No matter where you are on your coding journey, these challenge sites can help you grow your skills, prepare for interviews, and have some fun along the way. Happy coding!
LeetCode
This platform has a vast collection of challenges that you can solve in various programming languages. It's widely used for interview preparation, especially for jobs in big tech companies.
HackerRank also has a large collection of problems, and it supports a wide range of programming languages. Problems are categorized by difficulty and topic.
This is a competitive programming website where you can participate in regular contests and solve problems of varying difficulty levels.
TopCoder is one of the original online competitive programming platforms. It hosts weekly competitions in algorithms, data structures, and other computer science topics.
On Codewars, you can improve your skills by training with others on real code challenges called "kata".
This site is unique in that it offers mathematically-oriented problems. It's great for people who love both math and programming.
Exercism offers code practice and mentorship. You can solve the exercises and submit them, then receive feedback from mentors.
CodeChef is an Indian-based competitive programming website that provides a platform for coders to enhance their skills.
A competitive programming platform from Japan. They organize regular contests.
This site offers coding challenges in Java and Python. The problems are smaller than what you'd find on other sites, but it's great for daily practice and learning syntax.
Coderbyte offers a collection of coding challenges that you can solve directly on the site in one of many programming languages. They also offer solutions and a discussion board to learn from others.
Kattis provides a wide range of problems from past coding competitions. Problems are ranked by difficulty, from novice to expert.
A platform for learning bioinformatics through problem solving. It offers a collection of challenges that grow in difficulty, teaching you new concepts along the way.
This site offers a wide variety of problems, from beginner to advanced, that you can solve in many programming languages.
CodeSignal has a wide variety of challenges and also includes interview practice sections specifically designed for certain companies.
Edabit offers a variety of challenges in several different languages, along with solutions and user discussions.
Firecode.io offers a collection of challenges and full course study plans specifically tailored for interview prep.
This service emails you one coding problem per day, which you can solve in any language.
InterviewBit features programming and interview preparation questions, often directly related to questions asked in technical interviews at tech companies.
This platform provides a curated list of questions classified by difficulty and category, along with video explanations. It's primarily focused on interview prep.
GeeksforGeeks has a massive collection of problems along with their solutions. They also provide a lot of learning resources.
Hackerearth offers coding challenges and also hosts hackathons.
While not a traditional competitive coding site, Kaggle offers machine learning competitions where you write code to predict data.
Pramp is specifically focused on interview preparation. It offers peer-to-peer mock interviews where you can practice both coding and interviewing skills.
E-Olymp offers a large set of problems primarily for students involved in Olympiad programming.
Exercism offers over 3100 challenges spanning 52 different programming languages. You can work on the challenges on your machine using Exercism's own command line interface. What makes Exercism unique is that you get to work with a mentor who reviews your solutions and helps you improve them. Once your solutions have been approved, you unlock more challenges​.
SPOJ offers more than 20,000 coding challenges that can be solved in an online editor. They also host their own coding contests and provide a platform for users to discuss coding challenges. However, they currently don't provide any official solutions or editorials​1​.
CodinGame offers a unique take on coding challenges. Instead of simply solving challenges in an editor, you actually write the code for games that you play directly online. You can write your code in one of over 20 programming languages. Despite being different from typical competitive programming websites, CodinGame is popular among programmers who enjoy solving challenges and participating in contests​.