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    This article is in need of a technical review.

    The bound() method of the IDBKeyRange interface creates a new key range with upper and lower bounds.

    The bounds can be open (that is, the bounds exclude the endpoint values) or closed (that is, the bounds include the endpoint values). By default, the bounds are closed.


    myKeyRange = IDBKeyRange.bound("A", "Z", true, true);


    IDBKeyRange: The newly created key range.


    This method may raise a DOMException with a DOMError of the following type:

    Exception Description

    The following conditions raise an exception:

    • The lower or upper parameters were not passed a valid key.
    • The lower key is greater than the upper key.
    • The lower key and upper key match and either of the bounds are open.


    The following example illustrates how you'd use a bound key range. Here we declare a keyRangeValue = IDBKeyRange.bound("A", "F"); — a range between values of "A" and "F". We open a transaction (using IDBTransaction) and an object store, and open a Cursor with IDBObjectStore.openCursor, declaring keyRangeValue as its optional key range value. This means that the cursor will only retrieve records with keys inside that range. This range includes the values "A" and "F", as we haven't declared that they should be open  bounds. If we used IDBKeyRange.bound("A", "F", true, true);, then the range would not include "A" and "F", only the values between them.

    Note: For a more complete example allowing you to experiment with key range, have a look at our IDBKeyRange-example repo (view the example live too.)

    function displayData() {
      var keyRangeValue = IDBKeyRange.bound("A", "F");
      var transaction = db.transaction(['fThings'], 'readonly');
      var objectStore = transaction.objectStore('fThings');
      objectStore.openCursor(keyRangeValue).onsuccess = function(event) {
        var cursor =;
          if(cursor) {
            var listItem = document.createElement('li');
            listItem.innerHTML = '<strong>' + cursor.value.fThing + '</strong>, ' + cursor.value.fRating;
          } else {
            console.log('Entries all displayed.');


    The lower bound of the key range.
    The upper bound of the key range.
    Optional. If false (default value), the range includes the lower bound value of the key range.
    Optional. If false (default value), the range includes the upper bound value of the key range.


    Specification Status Comment
    Indexed Database API
    The definition of 'bound()' in that specification.
    Candidate Recommendation  

    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
    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 Not supported

    See also

    Document Tags and Contributors

    Contributors to this page: trevorh, fscholz, chrisdavidmills
    Last updated by: fscholz,