IDBDatabase: createObjectStore() method

Note: This feature is available in Web Workers.

The createObjectStore() method of the IDBDatabase interface creates and returns a new IDBObjectStore.

The method takes the name of the store as well as a parameter object that lets you define important optional properties. You can use the property to uniquely identify individual objects in the store. As the property is an identifier, it should be unique to every object, and every object should have that property.

This method can be called only within a versionchange transaction.


createObjectStore(name, options)



The name of the new object store to be created. Note that it is possible to create an object store with an empty name.

options Optional

An options object whose attributes are optional parameters to the method. It includes the following properties:

keyPath Optional

The key path to be used by the new object store. If empty or not specified, the object store is created without a key path and uses out-of-line keys. You can also pass in an array as a keyPath.

autoIncrement Optional

If true, the object store has a key generator. Defaults to false.

Return value


This method may raise a DOMException with a name of one of the following types:

InvalidStateError DOMException

Thrown if the method was not called from a versionchange transaction callback.

TransactionInactiveError DOMException

Thrown if a request is made on a source database that does not exist (for example, when the database has been deleted or removed). In Firefox previous to version 41, an InvalidStateError was raised in this case as well, which was misleading; this has now been fixed (see Firefox bug 1176165).

ConstraintError DOMException

Thrown if an object store with the given name (based on a case-sensitive comparison) already exists in the connected database.

InvalidAccessError DOMException

Thrown if autoIncrement is set to true and keyPath is either an empty string or an array containing an empty string.


// Let us open our database
const request ="toDoList", 4);

// This handler is called when a new version of the database
// is created, either when one has not been created before
// or when a new version number is submitted by calling
// This handler is only supported in recent browsers.
request.onupgradeneeded = (event) => {
  const db =;

  db.onerror = (event) => {
    note.innerHTML += "<li>Error loading database.</li>";

  // Create an objectStore for this database

  const objectStore = db.createObjectStore("toDoList", {
    keyPath: "taskTitle",

  // define what data items the objectStore will contain

  objectStore.createIndex("hours", "hours", { unique: false });
  objectStore.createIndex("minutes", "minutes", { unique: false });
  objectStore.createIndex("day", "day", { unique: false });
  objectStore.createIndex("month", "month", { unique: false });
  objectStore.createIndex("year", "year", { unique: false });

  objectStore.createIndex("notified", "notified", { unique: false });

  note.innerHTML += "<li>Object store created.</li>";


Indexed Database API 3.0
# ref-for-dom-idbdatabase-createobjectstore①

Browser compatibility

BCD tables only load in the browser

See also