WeCode
Academy
Tutorials
Web Development
Bootstrap
CSS
HTML
JavaScript
jQuery
Node.js
PHP
React
TypeScript
Programming
C
C#
C++
Go
Java
Python
Rust
Data and Databases
NumPy
Pandas
SQL
Tools
Bash
Git
Projects
Project: A Tiny Shell in C
Project: Bank Account System
Project: Library Management System
Project: Portfolio Page
Project: Quiz App in React
Project: Sales Data Analysis
Project: Server Log Analyser
Project: To-Do REST API
Project: URL Shortener
Project: Word Counter in Four Languages
All tutorials ❯
Paths
References
Practice
Try it editor
Quizzes
How To recipes
Tools
Glossary
My Learning
🌙
Dark mode
Home
›
How To
›
JavaScript
Count how many times each item appears
Use reduce to build a tally object.
Example
javascript
const words = ["a", "b", "a", "c", "b", "a"]; const counts = words.reduce((acc, w) => { acc[w] = (acc[w] || 0) + 1; return acc; }, {}); console.log(counts);
Run ❯
Reset
Open in editor »
More JavaScript recipes
Copy text to the clipboard
Debounce a function
Loop over an object
Remove duplicates from an array
Shuffle an array
WeCodeAcademyWeCodeAcademy