The clear() method of the IDBObjectStore interface creates and immediately returns an IDBRequest object, and clears this object store in a separate thread. This is for deleting all the current data out of an object store.

Clearing an object store consists of removing all records from the object store and removing all records in indexes that reference the object store.

Note: This feature is available in Web Workers.


var request = objectStore.clear();


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
ReadOnlyError The transaction associated with this operation is in read-only mode.
TransactionInactiveError This IDBObjectStore's transaction is inactive.


In the following code snippet, we open a read/write transaction on our database and clear all the current data out of the object store using clear(). For a full working example, see our To-do Notifications app (view example live.)

// Let us open our database
var DBOpenRequest ="toDoList", 4);

DBOpenRequest.onsuccess = function(event) {
  note.innerHTML += '<li>Database initialised.</li>';
  // store the result of opening the database in the db variable. This is used a lot below
  db = DBOpenRequest.result;
  // Run the clearData() function to clear all the data form the object store

function clearData() {
  // open a read/write db transaction, ready for clearing the data
  var transaction = db.transaction(["toDoList"], "readwrite");

  // report on the success of opening the transaction
  transaction.oncomplete = function(event) {
    note.innerHTML += '<li>Transaction completed: database modification finished.</li>';

  transaction.onerror = function(event) {
    note.innerHTML += '<li>Transaction not opened due to error: ' + transaction.error + '</li>';

  // create an object store on the transaction
  var objectStore = transaction.objectStore("toDoList");

  // clear all the data out of the object store
  var objectStoreRequest = objectStore.clear();

  objectStoreRequest.onsuccess = function(event) {
    // report the success of our clear operation
    note.innerHTML += '<li>Data cleared.</li>';


Specification Status Comment
Indexed Database API
The definition of 'clear()' in that specification.
Editor's Draft  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 23webkit
10 moz
16.0 (16.0)
10, partial 15 7.1
Available in workers (Yes) 37.0 (37.0) ? (Yes) ?
Feature Android Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile
Basic support 4.4 22.0 (22.0) 1.0.1 10 22 8
Available in workers (Yes) 37.0 (37.0) (Yes) ? (Yes) ?

See also

Document Tags and Contributors

 Contributors to this page: jpmedley, inexorabletash, chrisdavidmills, fscholz
 Last updated by: jpmedley,