Web Storage
localStorage stores data permanently; sessionStorage clears when the tab closes. Both store string key-value pairs.
HTML
Beginner
3 min read
Web Storage API
Example
// Store
localStorage.setItem("theme", "dark");
sessionStorage.setItem("step", "2");
// Read
const theme = localStorage.getItem("theme"); // "dark"
const step = sessionStorage.getItem("step"); // "2"
// Store objects (JSON)
localStorage.setItem("user", JSON.stringify({ id: 1, name: "Alice" }));
const user = JSON.parse(localStorage.getItem("user"));
// Delete
localStorage.removeItem("theme");
localStorage.clear(); // all Pro Tip
Web Storage is synchronous — avoid storing large data; use IndexedDB for complex datasets.