Kata Library: JavaScript Practice
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
22
Arrays
32
Binary Trees
2
Compilers
1
Data Structures
21
Functional Programming
74
Fundamentals
74
Lists
9
Mathematics
1
Recursion
1
Regular Expressions
4
Sorting
1
Strings
19
Trees
2
FEATURED TAGS
Cryptography
Data Science
Debugging
Games
Tutorials
74 Kata Found
7 kyu
Homogenous arrays
4,424
lilsweetcaligula
Arrays
Fundamentals
Functional Programming
7 kyu
Coding Meetup #4 - Higher-Order Functions Series - Find the first Python developer
10,310
PiotrBerebecki
Functional Programming
Data Structures
Arrays
Fundamentals
Algorithms
Strings
Regular Expressions
7 kyu
Coding Meetup #2 - Higher-Order Functions Series - Greet developers
12,774
PiotrBerebecki
Data Structures
Fundamentals
Algorithms
Strings
Regular Expressions
Arrays
Functional Programming
7 kyu
Coding Meetup #1 - Higher-Order Functions Series - Count the number of JavaScript developers coming from Europe
16,502
PiotrBerebecki
Data Structures
Fundamentals
Algorithms
Strings
Regular Expressions
Arrays
Functional Programming
7 kyu
Sum of Odd Cubed Numbers
11,606
elliottmck
5 Issues Reported
Fundamentals
Functional Programming
Arrays
7 kyu
Coding Meetup #3 - Higher-Order Functions Series - Is Ruby coming?
11,082
PiotrBerebecki
Data Structures
Fundamentals
Algorithms
Strings
Regular Expressions
Arrays
Functional Programming
7 kyu
Unpacking Arguments
13,392
user578387
1 Issue Reported
Functional Programming
Fundamentals
6 kyu
Once
6,191
osuushi
3 Issues Reported
Functional Programming
Fundamentals
7 kyu
Functional Addition
18,735
amrdraz
Functional Programming
Fundamentals
6 kyu
Unary function chainer
7,249
tpatja
Functional Programming
Fundamentals
7 kyu
First-Class Function Factory
7,625
otajor
Fundamentals
Functional Programming
Arrays
7 kyu
Pair Zeros
2,365
Nianpeng
Algorithms
Arrays
Fundamentals
Functional Programming
7 kyu
Currying functions: multiply all elements in an array
16,209
limeyb7
1 Issue Reported
Functional Programming
Fundamentals
7 kyu
Coding Meetup #17 - Higher-Order Functions Series - Sort by programming language
2,155
PiotrBerebecki
Functional Programming
Data Structures
Arrays
Fundamentals
Algorithms
Sorting
6 kyu
A functional deck of cards....
878
thatrubylove
5 Issues Reported
Functional Programming
Fundamentals
6 kyu
Fun with lists: map
1,701
janitormeir
Lists
Functional Programming
Fundamentals
8 kyu
The 'if' function
34,287
user578387
10 Issues Reported
Functional Programming
Fundamentals
7 kyu
Coding Meetup #5 - Higher-Order Functions Series - Prepare the count of languages
8,274
PiotrBerebecki
Functional Programming
Data Structures
Arrays
Fundamentals
Algorithms
6 kyu
"Stringing"+"Me"+"Along"
6,930
shinchy
Functional Programming
Fundamentals
7 kyu
Spanish Conjugator
1,206
Phares
Strings
Arrays
Functional Programming
Fundamentals
6 kyu
Temperature converter
1,006
kusm
5 Issues Reported
Functional Programming
Data Structures
Strings
Mathematics
Fundamentals
5 kyu
Lambda Calculus: Lists
111
Freddie C
Functional Programming
Fundamentals
Lists
Data Structures
7 kyu
Map function issue
1,223
bereket2015
3 Issues Reported
Functional Programming
Arrays
Fundamentals
7 kyu
Pluck
5,964
osuushi
1 Issue Reported
Functional Programming
Arrays
Fundamentals
7 kyu
Adding useful functional functionality to JavaScript arrays
4,010
r0ze
Functional Programming
Fundamentals
7 kyu
Flatten
12,812
xcthulhu
1 Issue Reported
Functional Programming
Arrays
Fundamentals
7 kyu
esreveR
10,916
xcthulhu
1 Issue Reported
Functional Programming
Fundamentals
6 kyu
Function composition
9,462
matthewglover
1 Issue Reported
Functional Programming
Fundamentals
5 kyu
Fun with lists: trees edition
306
janitormeir
Trees
Lists
Functional Programming
Fundamentals
Binary Trees
Data Structures
Algorithms
7 kyu
Fun with lists: anyMatch + allMatch
1,148
janitormeir
1 Issue Reported
Lists
Functional Programming
Fundamentals
Loading...
Confirm
Collect:
undefined
Loading collection data...