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
113
Arrays
15
Binary
2
Ciphers
2
Cryptography
2
Data Structures
11
Date Time
2
Domain Specific Languages
1
Esoteric Languages
1
Filtering
2
Functional Programming
4
Fundamentals
26
Interpreters
1
Logic
4
Mathematics
4
Number Theory
1
Parsing
10
Performance
2
Puzzles
5
Recursion
2
Regular Expressions
113
Restricted
2
Security
2
Stacks
2
State Machines
2
Strings
68
Trees
1
FEATURED TAGS
Cryptography
Data Science
Debugging
Games
Tutorials
113 Kata Found
6 kyu
Valid Phone Number
21,016
xDranik
2 Issues Reported
Regular Expressions
Algorithms
Beta
Validate the Euro bill
28
Aza_rt
Status:
Awaiting approval
Estimated Rank:
7 kyu
Regular Expressions
Algorithms
6 kyu
Split Strings
167,137
jhoffner
Regular Expressions
Strings
Algorithms
5 kyu
ISBN-10 Validation
11,408
nklein
4 Issues Reported
Regular Expressions
Algorithms
6 kyu
FIRE and FURY
1,322
dinglemouse
1 Issue Reported
Regular Expressions
Strings
Algorithms
5 kyu
Return substring instance count - 2
3,179
ineiti
2 Issues Reported
Strings
Regular Expressions
Algorithms
Beta
Spanish DNI Validation Algorithm
26
adnan.ha
Status:
Testing & feedback needed
Estimated Rank:
6 kyu
Algorithms
Regular Expressions
7 kyu
Password validator
8,203
tdowek1
1 Issue Reported
Fundamentals
Regular Expressions
Algorithms
7 kyu
80's Kids #5: You Can't Do That on Television
1,690
NateBrady23
1 Issue Reported
Fundamentals
Algorithms
Strings
Regular Expressions
7 kyu
Coding Meetup #3 - Higher-Order Functions Series - Is Ruby coming?
10,977
PiotrBerebecki
Data Structures
Fundamentals
Algorithms
Strings
Regular Expressions
Arrays
Functional Programming
7 kyu
UVB-76 Message Validator
1,116
Drymonade
Algorithms
Strings
Regular Expressions
6 kyu
Linux history and `!` command. Series#5 The `!?string` command
299
nbeck
1 Issue Reported
Strings
Parsing
Regular Expressions
Algorithms
6 kyu
Linux history and `!` command. Series#4 The `!string` command
292
nbeck
3 Issues Reported
Strings
Parsing
Regular Expressions
Algorithms
6 kyu
Linux history and `!` command. Series#3 The `!-n` command
301
nbeck
3 Issues Reported
Strings
Parsing
Regular Expressions
Algorithms
6 kyu
Linux history and `!` command. Series#2 The `!n` command
412
nbeck
Strings
Parsing
Regular Expressions
Algorithms
6 kyu
Linux history and `!` command. Series#1 The `!!` command
640
nbeck
Strings
Parsing
Regular Expressions
Algorithms
7 kyu
Is that a real phone number? (British version)
1,436
lucyrose93
1 Issue Reported
Regular Expressions
Strings
Algorithms
6 kyu
Convert string to camel case
203,890
jhoffner
20 Issues Reported
Regular Expressions
Algorithms
Strings
5 kyu
Word Finder
2,042
BattleRattle
Strings
Regular Expressions
Filtering
Algorithms
Beta
The Lost Message 🧐
6
AVElfallah
Status:
Testing & feedback needed
Estimated Rank:
5 kyu
Algorithms
Puzzles
Fundamentals
Regular Expressions
6 kyu
Simple Barcode Scanner
262
furbrain
1 Issue Reported
Regular Expressions
Algorithms
7 kyu
Remove consecutive duplicate words
7,764
e.mihaylin
Strings
Regular Expressions
Algorithms
6 kyu
Converting Measures
472
PollyRibeiro
Regular Expressions
Algorithms
6 kyu
Vowel Shifting
1,547
user5036852
1 Issue Reported
Strings
Regular Expressions
Algorithms
6 kyu
Trumpness detector
1,140
GiacomoSorbi
3 Issues Reported
Regular Expressions
Strings
Algorithms
6 kyu
Evil Autocorrect Prank
5,264
yaphi1
3 Issues Reported
Strings
Regular Expressions
Algorithms
6 kyu
Coordinates Validator
7,018
louy
8 Issues Reported
Regular Expressions
Algorithms
5 kyu
ROT13
28,609
hvaara
Strings
Ciphers
Regular Expressions
Algorithms
6 kyu
Pete's inappropriate speech
375
GiacomoSorbi
1 Issue Reported
Regular Expressions
Strings
Algorithms
5 kyu
Simple Pig Latin
170,673
user2505876
11 Issues Reported
Regular Expressions
Algorithms
Loading...
Confirm
Collect:
undefined
Loading collection data...