Practice Arena

Python Coding
Challenges

Write real Python in the browser. Instant feedback. From beginner to expert.

925 challenges 556 easy 323 medium 46 hard

All Easy Medium Hard

All Python Basics Strings & Text Lists & Arrays Dicts & Sets Functions & Closures OOP & Classes Data Structures & Algorithms Advanced Python Iterators & Generators Decorators & Context Managers Error Handling & Exceptions Regular Expressions Math & Number Theory Bit Manipulation Dynamic Programming Trees & Binary Trees Graphs & Graph Algorithms Recursion & Backtracking Greedy Algorithms Binary Search Two Pointers & Sliding Window Stacks & Queues Heaps & Priority Queues Linked Lists Matrix & 2D Arrays Datetime & Time Calculations Data Formats & Parsing SQL & SQLite Numpy & Vectorized Computing Cryptography & Hashing

OOP & Classes medium

Complex Number Class

Implement a Complex class supporting addition, subtraction, multiplication, division, equality, and string formatting.

classes magic-methods arithmetic

Advanced Python medium

TypeVar bounded generic

Learn to use TypeVar with bounds to write type-safe generic functions in Python.

generics typevar typing

Advanced Python medium

Descriptor Property

Create a descriptor class that ensures attribute values are positive integers.

descriptors oop python-advanced

Math & Number Theory medium

Correlation Coefficient

Write a pure-Python function that computes the Pearson correlation coefficient between two lists of numbers.

statistics math arrays

Binary Search medium

Interpolation Search

Implement interpolation search in Python on a sorted list of integers.

search sorted-array binary-search

Data Formats & Parsing medium

Serialize dict to TOML-like

Convert nested Python dicts into a simplified TOML-like string with sorted keys, type-aware formatting, and flat table sections.

dict toml serialization

SQL & SQLite medium

Nth Highest Salary

Write a Python function using SQLite to return the Nth highest distinct salary from an employee table.

sql sqlite aggregation

Showing 1–7 of 7 challenges · medium

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.