Maintenance

Site is under maintenance — quizzes are still available.

Go to quizzes
Practice Arena

Python Coding Challenges

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

57 challenges 26 easy 23 medium 8 hard
Python Basics easy

FizzBuzz, precisely

Return a newline-separated string for 1..n: Fizz, Buzz, FizzBuzz, or the number.

control flow strings modulo
2
+10 pts 12m
Strings & Text easy

Reverse a string

Return the characters of the string in reverse order.

strings slicing
+5 pts 5m
Strings & Text easy

Palindrome check

Return True if the string reads the same forwards and backwards (ignoring case and non-alphanumeric).

strings two-pointer
+8 pts 8m
Strings & Text easy

Count vowels

Count the number of vowels (a, e, i, o, u) in a string (case-insensitive).

strings counting
+5 pts 5m
Strings & Text easy

Title case converter

Return the string with each word capitalised.

strings split
+5 pts 5m
Strings & Text easy

Anagram check

Return True if two strings are anagrams of each other.

strings sorting counter
+10 pts 10m
Strings & Text medium

Run-length encoding

Compress consecutive identical characters, e.g. 'aaabbc' → 'a3b2c1'.

strings compression
+20 pts 20m
Strings & Text medium

Longest common prefix

Find the longest common prefix among a list of strings.

strings zip
+18 pts 18m
Strings & Text medium

Integer to Roman

Convert a positive integer to its Roman numeral representation.

strings greedy
+22 pts 22m
Strings & Text medium

Zigzag string conversion

Encode a string in zigzag order across numRows rows, then read row by row.

strings math
+22 pts 20m
Dicts & Sets medium

Group anagrams

Group words that are anagrams of each other.

dict sorting strings
+22 pts 20m
Dicts & Sets easy

First non-repeating character

Find the index of the first character that appears only once.

dict strings counter
1
+12 pts 12m
Data Structures & Algorithms easy

Valid parentheses

Return True if brackets in the string close in the correct order.

stack strings
+15 pts 14m
Data Structures & Algorithms hard

Word ladder length

Return the length of the shortest transformation from beginWord to endWord changing one letter at a time.

BFS graph strings
+45 pts 40m

Showing 14 challenges

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

  1. Pick a category — basics, algorithms, strings, and more
  2. Open a challenge, read the statement, and edit the starter code
  3. 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.