The count() method of the IDBObjectStore interface returns an IDBRequest object, and, in a separate thread, returns the total number of records that match the provided key or IDBKeyRange. If no arguments are provided, it returns the total number of records in the store.

Note: This feature is available in Web Workers


var request = ObjectStore.count();
var request = ObjectStore.count(query);


query Optional

A key or IDBKeyRange object that specifies a range of records you want to count.

Return value

An IDBRequest object on which subsequent events related to this operation are fired.


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

Exception Description
InvalidStateError This IDBObjectStore has been deleted.
TransactionInactiveError This IDBObjectStore's transaction is inactive.
DataError The specified key or key range is invalid.


In this simple fragment we create a transaction, retrieve an object store, then count the number of records in the store using count() — when the success handler fires, we log the count value (an integer) to the console.

var transaction = db.transaction(['fThings'], 'readonly');
var objectStore = transaction.objectStore('fThings');

var countRequest = objectStore.count();
countRequest.onsuccess = function() {


Indexed Database API 3.0 (Indexed DB 3.0)
# ref-for-dom-idbobjectstore-count①

Browser compatibility

BCD tables only load in the browser

See also