The Scanner class

A Scanner object is used to scan for LE devices which are broadcasting advertising data. In most situations this will give a set of devices which are available for connection. (Note, however, that Bluetooth LE devices may accept connections without broadcasting advertising data, or may broadcast advertising data but may not accept connections).



Creates and initialises a new scanner object. index identifies the Bluetooth interface to use (where 0 is /dev/hci0 etc). Scanning does not start until the start() or scan() methods are called - see below for details.

Instance Methods


Stores a reference to a delegate object, which receives callbacks when broadcasts from devices are received. See the documentation for DefaultDelegate for details.

scan([timeout = 10])

Scans for devices for the given timeout in seconds. During this period, callbacks to the delegate object will be called. When the timeout ends, scanning will stop and the method will return a list (or a view on Python 3.x) of ScanEntry objects for all devices discovered during that time.

scan() is equivalent to calling the clear(), start(), process() and stop() methods in order.


Clears the current set of discovered devices.


Enables reception of advertising broadcasts from peripherals. Should be called before calling process().

process([timeout = 10])

Waits for advertising broadcasts and calls the delegate object when they are received. Returns after the given timeout period in seconds. This may be called multiple times (between calls to start() and stop() ).


Disables reception of advertising broadcasts. Should be called after process() has returned.


Returns a list (a view on Python 3.x) of ScanEntry objects for all devices which have been discovered (since the last clear() call).

Sample code

Basic code to run a LE device scan follows this example:

from bluepy.btle import Scanner, DefaultDelegate

class ScanDelegate(DefaultDelegate):
    def __init__(self):

    def handleDiscovery(self, dev, isNewDev, isNewData):
        if isNewDev:
            print "Discovered device", dev.addr
        elif isNewData:
            print "Received new data from", dev.addr

scanner = Scanner().withDelegate(ScanDelegate())
devices = scanner.scan(10.0)

for dev in devices:
    print "Device %s (%s), RSSI=%d dB" % (dev.addr, dev.addrType, dev.rssi)
    for (adtype, desc, value) in dev.getScanData():
        print "  %s = %s" % (desc, value)

NOTE that LE scanning must be run as root.

See the documentation for ScanEntry for the information available via the dev parameter passed to the delegate.