Eddystone UID

The UID is a characteristic of Eddystone that identifies each beacon. The broadcasted signal is received by a device which can then determine the action to be initiated. The UID behaves in a similar way to that of the iBeacons UUID, however instead of containing a UUID, major and minor values, the UID is split into 2 different parts: the Namespace and Instance. Please check the notes at the bottom of the page before configuration.

To set a UID

1. Download the AprilBeacon App.
2. Open it and select ‘Bluetooth’.
3. Ensure the battery is inserted into the Beacon the correct way, then refresh the app by pulling down and tap on the beacon.
4. Change the type of beacon to 'Eddystone UID' from the ‘Broadcast Type Menu’.
5. Input the UUID to what you have configured in your App, in the Proximity UUID field.

The Proximity UUID is made up of the Namespace and Instance, in our Beacon this is input together as a 32 character value. The first 20 characters are made up of the Namespace, and the next 12 are the Instance. They are split at intervals by a dash (‘-‘). For example: 

Namespace: 9E5D61E66621DA7CA630
Instance: 0EDY45673A89
Proximity UUID: 9E5D61E6-6621-DA7C-A630-0EDY45673A89

6. Tap ‘Save’ in the top right to save the configuration. 
7. You will then be prompted to input a password, by default it is: ‘AprilBrother'.
8. The Beacon will refresh and begin to transmit.

Click here to test that your Eddystone is broadcasting.



The Namespace acts like an iBeacon UUID specifying the beacons to one particular company or organisation. The Namespace can be made in two ways. Either your own secure URL can be used (truncated hash of your FQDN), or elided UUID. It is a way of ensuring that each Beacon in use has its own unique UID. 

Method 1 - Converting URL to SHA-1

The best way to create a Namespace is to convert your own secure URL to a SHA-1 hash, then selecting the first 10 bytes. For example: avvel.co.uk would have a Namespace of ‘9E5D61E66621DA7CA630’ (Click here to find out how to generate the Namespace)

Method 2 - Elided Version 4 UUID

This method may be used if a company or organisation already has its own UUID. To create a Namespace from a UUID you need to remove the 3 sets of 4 characters from the middle of the UUID. For example if your UUID was '8b0ca750-e7a7-4e14-bd99-095477cb3e77', then you would need to remove 'e7a7-4e14-bd99', and so you would be left with 8b0ca750095477cb3e77 as your Namespace.


The Instance part of the UID is similar to that of the Major and Minor Values, in respect to the fact that it is specific to a singe Beacon. Like with iBeacons, it can be used to identify beacons in a specific location, the number may be random, sequential, hierarchical, or any other scheme.