Note: This feature is available in Web Workers.

The IDBFactory interface of the IndexedDB API lets applications asynchronously access the indexed databases. The object that implements the interface is window.indexedDB. You open — that is, create and access — and delete a database with this object, and not directly with IDBFactory.

Instance methods

Requests opening a connection to a database.


Requests the deletion of a database.


Compares two keys and returns a result indicating which one is greater in value.


Returns a promise that fulfills with an array of all available databases, including their names and versions.


In the following code snippet, we make a request to open a database, and include handlers for the success and error cases. For a full working example, see our To-do Notifications app (view example live).

// Let us open version 4 of our database
const DBOpenRequest ="toDoList", 4);

// these two event handlers act on the database being opened successfully, or not
DBOpenRequest.onerror = (event) => {
  console.error("Error loading database.");

DBOpenRequest.onsuccess = (event) => {"Database initialized.");

  // store the result of opening the database in the db variable. This is used a lot later on, for opening transactions and suchlike.
  db = DBOpenRequest.result;


Indexed Database API 3.0
# factory-interface

Browser compatibility

BCD tables only load in the browser

See also