webble is a client-side utility which facilitates pairing and exchanging data with BLE devices using the Web Bluetooth API.
webble is lightweight client-side JavaScript that runs in the browser. See a live demo using the code in this repository at: reelyactive.github.io/webble
Include in an index.html file the webble.js script:
<html>
<head></head>
<body>
<button id="startbutton"> Start </button>
<script src="js/webble.js"></script>
<script src="js/app.js"></script>
</body>
</html>Include in a js/app.js the code to connect to a Bluetooth Low Energy device using webble:
const REQUEST_OPTIONS = { acceptAllDevices: true };
startbutton.addEventListener('click', () => {
webble.requestDeviceAndConnect(REQUEST_OPTIONS, (error) => {
/* Read and write characteristics, etc. */
});
});Open the index.html file in a web browser and click Start for webble to begin scanning for Bluetooth Low Energy devices in range.
webble supports the following functions which are essentially convenience wrappers around a subset of the Web Bluetooth API methods, using callbacks rather than Promises.
webble.isAvailable((isAvailable) => {
if(isAvailable) { /* Web Bluetooth is supported by this browser */ }
else { /* Web Bluetooth is NOT supported by this browser */ }
});const REQUEST_OPTIONS = { /* See below */ };
webble.requestDeviceAndConnect(REQUEST_OPTIONS, (error) => {
if(error) { /* The connection was unsuccessful */ }
else { /* webble.device is connected */ }
});For a complete definition of REQUEST_OPTIONS, see the MDN web docs for requestDevice().
webble.on('connect', (device) => {});
webble.on('disconnect', () => {});webble.discoverServicesAndCharacteristics((error) => {
if(!error) {
/* webble.device.services and webble.device.characteristics populated */
}
});let uuid = '6e400001-b5a3-f393-e0a9-e50e24dcca9e';
webble.readCharacteristic(uuid, (error, value) => {
if(!error) { /* value is a DataView */ }
});let uuid = '6e400001-b5a3-f393-e0a9-e50e24dcca9e';
let value = Uint8Array.of(123); // Value must be a typed array
webble.writeCharacteristic(uuid, value, (error) => {
if(!error) { /* Characteristic write successful */ }
});webble.disconnect();| Variable | Type | Description |
|---|---|---|
webble.device |
Object | Subset of BluetoothDevice, adding services & characteristics, each as a Map |
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MIT License
Copyright (c) 2025 reelyActive
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