Kata Library
Sign Up
Time to claim your honor
Training
Practice
Complete challenging
Kata
to earn honor and ranks. Re-train to hone technique
Freestyle Sparring
Take turns remixing and refactoring others code through
Kumite
Community
Leaderboards
Achieve honor and move up the global leaderboards
Chat
Join our
Discord
server and chat with your fellow code warriors
Discussions
View our
Github Discussions
board to discuss general Codewars topics
About
Docs
Learn about all of the different aspects of Codewars
Blog
Read the latest news from Codewars and the community
Log In
Sign Up
Library
Collections
Newest
Oldest
Popularity
Positive Feedback
Most Completed
Least Completed
Hardest
Easiest
Name
Relevance
Low Satisfaction
All
My Languages
Agda (Beta)
BF (Beta)
C
CFML (Beta)
Clojure
COBOL (Beta)
CoffeeScript
CommonLisp (Beta)
Coq
C++
Crystal
C#
D (Beta)
Dart
Elixir
Elm (Beta)
Erlang (Beta)
Factor (Beta)
Forth (Beta)
Fortran (Beta)
F#
Go
Groovy
Haskell
Haxe (Beta)
Idris (Beta)
Java
JavaScript
Julia (Beta)
Kotlin
λ Calculus (Beta)
Lean
Lua
NASM
Nim (Beta)
Objective-C (Beta)
OCaml (Beta)
Pascal (Beta)
Perl (Beta)
PHP
PowerShell (Beta)
Prolog (Beta)
PureScript (Beta)
Python
R (Beta)
Racket
Raku (Beta)
Reason (Beta)
RISC-V (Beta)
Ruby
Rust
Scala
Shell
Solidity (Beta)
SQL
Swift
TypeScript
VB (Beta)
Approved & Beta
Approved
Beta
All
Kata I have not trained on
Kata I have not completed
Kata I have completed
8 kyu
easiest
7 kyu
6 kyu
5 kyu
4 kyu
3 kyu
2 kyu
1 kyu
hardest
Algorithms
6
Arrays
9
Binary
1
Bits
1
Databases
4
Date Time
1
Debugging
4
Design Patterns
1
Dynamic Programming
1
Functional Programming
5
Fundamentals
10
Games
3
Geometry
1
Interpreters
1
Lists
1
Macros
1
Mathematics
6
Memoization
3
Metaprogramming
2
Object-oriented Programming
8
Parsing
1
Performance
4
Probability
1
Puzzles
4
Recursion
1
Refactoring
74
Restricted
6
SQL
5
Strings
3
Trees
2
FEATURED TAGS
Cryptography
Data Science
Debugging
Games
Tutorials
74 Kata Found
7 kyu
Balance the parentheses
963
SJFx
Refactoring
7 kyu
Time Converter: hours, minutes, seconds and milliseconds
1,182
srMarquinho
Date Time
Parsing
Refactoring
7 kyu
One line task: Square a number Without *, + or Math.pow()
377
Firefly2002
Refactoring
Mathematics
Games
Restricted
Puzzles
7 kyu
[BUG] XCOM-388: Mass spectrometer crashes
181
hobovsky
Debugging
Refactoring
7 kyu
Refactored Greeting
12,145
jhoffner
2 Issues Reported
Object-oriented Programming
Refactoring
5 kyu
Scytale encoder/decoder (ancient Spartans cipher)
104
lucky3
Fundamentals
Algorithms
Refactoring
5 kyu
Refactor a node-based calculator (DRY)
131
FArekkusu
Refactoring
Object-oriented Programming
Restricted
6 kyu
One line task: Multiples of 3 and 5
173
Firefly2002
Mathematics
Games
Refactoring
Algorithms
Restricted
Puzzles
6 kyu
One line task: Square Every Digit
1,143
Firefly2002
Puzzles
Games
Restricted
Refactoring
8 kyu
Be Concise I - The Ternary Operator
8,365
donaldsebleung
3 Issues Reported
Fundamentals
Refactoring
7 kyu
Rigged Dice
998
Scopula
Probability
Refactoring
7 kyu
Bug fix: Is this component visible?
116
dfhwze
Refactoring
Trees
Object-oriented Programming
4 kyu
Next bigger number with the same digits
39,909
GiacomoSorbi
5 Issues Reported
Strings
Refactoring
Beta
There can be only one: Numeric Extension
25
lucky3
Status:
Testing & feedback needed
Estimated Rank:
3 kyu
Refactoring
Beta
Refactor out a switch-statement to a Dictionary
75
dibley1973
3 Issues Reported
Status:
Testing & feedback needed
Estimated Rank:
7 kyu
Fundamentals
Refactoring
6 kyu
Refactor out a switch-statement using polymorphism
189
dibley1973
5 Issues Reported
Fundamentals
Refactoring
2 kyu
Power tower modulo m
356
ecolban
1 Issue Reported
Refactoring
7 kyu
Playing with cubes III
474
Jotha
2 Issues Reported
Mathematics
Refactoring
2 kyu
Assembler interpreter (part II)
2,814
ShinuToki
5 Issues Reported
Interpreters
Refactoring
8 kyu
Well of Ideas - Easy Version
36,666
PG1
4 Issues Reported
Fundamentals
Arrays
Strings
Refactoring
6 kyu
Which are in?
83,493
g964
7 Issues Reported
Arrays
Lists
Strings
Refactoring
8 kyu
Is n divisible by x and y?
132,044
naaz
1 Issue Reported
Refactoring
6 kyu
One Line : Bit Calculator
168
dke
Fundamentals
Refactoring
4 kyu
N Linear
526
coryshrmn
Algorithms
Mathematics
Refactoring
8 kyu
Be Concise IV - Index of an element in an array
8,520
donaldsebleung
4 Issues Reported
Refactoring
4 kyu
Memoized Log Cutting
1,536
AlejandorLazaro
Dynamic Programming
Memoization
Refactoring
7 kyu
Working with arrays I (and why your code fails in some katas)
5,208
Chrono79
1 Issue Reported
Fundamentals
Arrays
Refactoring
6 kyu
Refactoring SQL Queries: part 2 (Pagination Disaster)
133
bornForThis
SQL
Databases
Refactoring
5 kyu
Paginating a huge book
1,859
hexafraction
Performance
Refactoring
6 kyu
Surviving the Bloody Enterprise: A Time-Travel Adventure with Running Totals
64
bornForThis
SQL
Databases
Restricted
Refactoring
Loading...
Confirm
Collect:
undefined
Loading collection data...