BluetoothGattCharacteristic (Firefox OS)

This API is available on Firefox OS for internal applications only.

The BluetoothGattCharacteristic interface of the Web Bluetooth API represents a GATT service characteristic, which includes characteristic definition, value, properties and configuration info, and a list of descriptors that provide related information.

Interface overview

interface BluetoothGattCharacteristic
  readonly attribute BluetoothGattService service;
  [Cached, Pure] readonly attribute sequence<BluetoothGattDescriptor> descriptors;

  readonly attribute DOMString uuid;
  readonly attribute unsigned short instanceId;
  readonly attribute ArrayBuffer? value;
  [Cached, Constant] readonly attribute Permissions permissions;
  [Cached, Constant] readonly attribute GattCharacteristicProperties properties;
  [Cached, Pure]              attribute WriteType writeType;

  [NewObject] Promise<ArrayBuffer> readValue();
  [NewObject] Promise<void> writeValue(ArrayBuffer value);
  [NewObject] Promise<void> startNotifications();
  [NewObject] Promise<void> stopNotifications();
  [NewObject] Promise<BluetoothGattDescriptor> addDescriptor(DOMString uuid, Permissions permissions, ArrayBuffer value);


BluetoothGattCharacteristic.service Read only
Returns the BluetoothGattService that this characteristic belongs to.
BluetoothGattCharacteristic.descriptors Read only
Returns a cached array containing the BluetoothGattDescriptor objects that describe this characteristic.
BluetoothGattCharacteristic.uuid Read only
Returns a DOMString representing the UUID of this characteristic.
BluetoothGattCharacteristic.instanceId Read only
Returns a number representing the instance id of this characteristic.
BluetoothGattCharacteristic.value Read only
Returns The cached value of this characteristic. This value can be updated via the BluetoothGattCharacteristic.readValue() method, characteristic notification, or indication from the remote device.
BluetoothGattCharacteristic.permissions Read only
Returns a bit mask that describes the operations permitted on this characteristic. Read only
Returns a bit mask that describes how to use the characteristic value.
BluetoothGattCharacteristic.writeType Read only
Returns the type of write operation particular to this characteristic.


Reads the characteristic value from the remote device. The cached value property will also be updated after retrieving the value.
Writes the characteristic value to the GATT server. If the local device is the GATT client, the value will be written to the remote GATT server. On the other hand, if the local device is the GATT server, the value will be written to BluetoothGattCharacteristic.value.
Registers notifications/indications for this characteristic.
Unregisters notifications/indications for this characteristic.
Adds a descriptor to this characteristic.


Specification Status Comment
Web Bluetooth
The definition of 'BluetoothGattCharacteristic' in that specification.
Draft Rough draft; not part of any official specification yet. It should be discussed as part of the W3C's System Applications Working Group.

Browser Compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support No support No support No support No support No support
Feature Android Android Webview Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support No support No support No support 2.1 No support No support No support No support


See also

Using the Web Bluetooth API

Document Tags and Contributors

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