join() & Array/String Conversion in JavaScript
From the JavaScript Array Methods cheat sheet · Iteration Methods · verified Jul 2026
join() & Array/String Conversion
Convert array to string and vice versa
javascript
// Array to string
[1, 2, 3].join(); // '1,2,3'
[1, 2, 3].join(' - '); // '1 - 2 - 3'
[1, 2, 3].join(''); // '123'
// String to array
'1,2,3'.split(','); // ['1', '2', '3']
'hello'.split(''); // ['h', 'e', 'l', 'l', 'o']
Array.from('hello'); // ['h', 'e', 'l', 'l', 'o']🟢 Essential - Common for display and parsing
💡 join() array→string, split() string→array
📌 Default separator is comma for join()
⚡ Use template literals for complex formatting
🔗 Related: toString() for simple conversion