How to Use localStorage — How-To Guide

localStorage lets you store key-value pairs in the browser with no expiry date. Data persists across sessions.

API Methods

setItem(key, value) — store a value
getItem(key) — retrieve a value
removeItem(key) — delete a key
clear() — delete all keys

Storing Objects

localStorage only stores strings. Use JSON.stringify() to store objects and JSON.parse() to retrieve them.

Limits

localStorage is limited to ~5MB per origin. Don't store sensitive data — it's accessible via JavaScript.

// Store a value localStorage.setItem('theme', 'dark'); // Retrieve a value const theme = localStorage.getItem('theme'); // "dark" // Store an object const user = { name: 'Alice', age: 30 }; localStorage.setItem('user', JSON.stringify(user)); // Retrieve an object const savedUser = JSON.parse(localStorage.getItem('user')); console.log(savedUser.name); // "Alice" // Remove a key localStorage.removeItem('theme'); // Clear everything localStorage.clear();