All 10 Browser Storage & Web APIs questions
More in Browser Storage & Web APIs
What's the difference between localStorage and sessionStorage? Why can you only store strings in localStorage, and how do you store objects? What is the storage event and when does it fire? What are the size limits of localStorage compared to IndexedDB? How do cookies differ from localStorage for storing data? What is the Cache API and how does it relate to Service Workers? How does the Geolocation API work and what are its privacy implications? What does the Intersection Observer API do and why is it preferred over scroll event listeners? How do you check available and used storage quota in a browser?
Advertisement
JavaScript › Browser Storage & Web APIs

What is IndexedDB and how does it differ from a simple key-value store?

Intermediate

Answer

IndexedDB is a low-level, transactional NoSQL database built into the browser. It supports structured objects, indexes for fast querying by property, and versioned schema upgrades — well beyond a flat key-value store like localStorage.
const request = indexedDB.open('AppDB', 1);
request.onupgradeneeded = (e) => {
  const db = e.target.result;
  db.createObjectStore('notes', { keyPath: 'id' });
};
Real-world example Building an offline-first note-taking app that needs to query notes by date or tag.

Common follow-ups: Why does IndexedDB use events and transactions instead of simple async/await natively?

Design Patterns in JavaScript
All 10 Browser Storage & Web APIs questions