Collatz steps
Count how many steps the Collatz sequence takes to reach 1 from n.
Factorial (iterative)
Compute n! iteratively without recursion.
Power of two?
Return True if n is an exact power of 2.
GCD via Euclid
Compute the greatest common divisor of two positive integers.
Prime checker
Return True if n is a prime number.
Compound interest
Return the future balance after compound interest, rounded to two decimals.
Showing 6 challenges · easy
Guide: free Python coding challenges
Practice Python by solving problems
PythonSkillset challenges are hands-on coding exercises from beginner to advanced. Open a challenge, read the problem, write Python in the split-pane editor, and run tests with Pyodide — no install required.
How to use the arena
- Pick a category — basics, algorithms, strings, and more
- Open a challenge, read the statement, and edit the starter code
- Run tests, fix failures, then try a related quiz or tutorial lesson
Challenges vs tutorials and quizzes
Challenges test what you can build under constraints. For guided teaching, use our Python tutorials. For quick checks, try quizzes or copy snippets from code samples.