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

Linked Lists easy

Sum all node values

Add every integer payload in the list.

linked-list lists pointers

Datetime & Time Calculations easy

Datetime to Unix timestamp

Parse a datetime string and convert it to a Unix timestamp assuming UTC.

datetime parsing timestamp

SQL & SQLite easy

Cumulative Sum SQL

Write a SQL query to compute cumulative sales totals per product ordered by sale date.

sql window-functions running-total

Numpy & Vectorized Computing easy

Dot product of two vectors

Return sum of element-wise products.

vectors arrays numpy-style

Numpy & Vectorized Computing easy

Sum each matrix row

Given rows, return each row sum.

vectors arrays numpy-style

Numpy & Vectorized Computing easy

Sum each matrix column

Return column totals for a rectangular matrix.

vectors arrays numpy-style

Showing 25–30 of 30 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.