Where to Find the Serial Number of a Withings Device

The serial number — also called the MAC ID or MAC address — is the unique identifier of a Withings device. It is the value you use to activate a device, link it to a user, look it up in Fleet Management, and give to Withings support when you open a ticket.

This page tells you where to find it, both on the hardware and through the API, so you can guide a program member over the phone or resolve a case from your own back office.

Serial number format

A serial number is 12 hexadecimal characters and always starts with one of two Withings prefixes:

Prefix	Rendered without separators	Rendered with separators
00:24:E4	0024E4XXXXXX	00:24:E4:XX:XX:XX
A4:7E:FA	A47EFAXXXXXX	A4:7E:FA:XX:XX:XX

Both renderings designate the same device. The separators and the letter case depend on where the value was read — a label on the box, a screen on the device, the Withings App, or an API response.

warning

Before you compare a serial number against your own records, normalize it: strip the colons and lowercase (or uppercase) the whole string. A member reading 00:24:E4:69:B2:30 off a box and an API response containing 00:24:e4:69:b2:30 are the same device, and a raw string comparison will tell you otherwise.

Withings API endpoints that take a mac_address parameter — such as User v2 - activate, User v2 - link and Device v2 - endpartnerprogram — expect the colon-separated lowercase form, for example 00:24:e4:69:b2:30.

1. If the device is installed in the Withings App

When the device has been set up in the Withings App, the member can read the serial number from the app.

1. Open the Withings App.
2. Tap the Devices section in the upper-right corner.
3. Select the product.
4. The serial number appears under Advanced Settings.
5. Tap the MAC ID to copy it to the phone's clipboard — the member can then paste it into an email or a chat instead of reading it out character by character.

tip

Ask the member to paste the value rather than dictate it. 0 versus O and 8 versus B are the most common transcription errors when a serial number is read aloud.

2. If the device is not installed yet, or is never set up through the Withings App

On a device that has not been set up — including cellular devices provisioned through the API, which a member never installs themselves — the serial number is printed on a label. Its position depends on the product.

Device	On the packaging	Inside the battery compartment	On the bottom
BeamO	✓		✓
U-Scan	✓	✓
Body / Body+	✓	✓
Body Pro / Body Pro 2	✓	✓
Body Scan	✓		✓
Body Comp	✓	✓
Body Smart	✓		✓
Body Cardio	✓		✓
BPM Connect	✓		✓
BPM Core	✓		✓
BPM Pro / BPM Pro 2	✓		✓
Sleep / Sleep Analyzer	✓		✓
ScanWatch	✓
ScanWatch 2 / ScanWatch Light	✓
Steel HR / Steel HR Sport	✓
Pulse HR / Move	✓
Thermo	✓	✓

note

Older or discontinued products (Aura, Home, Activité, Pop, Go, Wireless Scale WS30, Smart Body Analyzer WS50, Smart Kid Scale, Smart Baby Monitor, Move ECG, and the wired BPM) also carry a label on the packaging, and in most cases inside the battery compartment. The full list is on the Withings support page.

3. Reading the serial number from the device screen

BeamO, ScanWatch, Steel HR and Pulse HR can display their own serial number. Ask the member to cycle through the device menus until the serial number appears.

The device shows only the last 6 characters, in the form XX:XX:XX. The 00:24:E4 prefix is omitted. Prepend it yourself to rebuild the full 12-character value:

Displayed on device:  69:B2:30
Full serial number:   00:24:E4:69:B2:30

If the device is one that uses the A4:7E:FA prefix, the reconstruction is ambiguous — read the full value from the Withings App instead.

4. Retrieving a serial number as a developer

You do not always need the member to look at their hardware. If the device is linked to a user, or if you shipped it yourself, you can retrieve the serial number through the API.

User v2 - getdevice

Call User v2 - getdevice with the user's access token to list the devices linked to that user:

curl --header "Authorization: Bearer YOUR_ACCESS_TOKEN" \
     --data "action=getdevice" \
     'https://wbsapi.withings.net/v2/user'

Each device in the response carries a model, a type, a deviceid, and — for advanced partners — the mac_address, alongside first_session_date and last_session_date.

note

mac_address, fw, network and last_used_network are returned to advanced partners only. If your application does not have that permission, getdevice still returns the deviceid, which identifies the device in the data you receive but is not the serial number printed on the label. Contact your Withings representative if you need mac_address access.

Store the serial number at shipment time

If you ship devices through the Logistics API, you never have to ask the member at all: the serial numbers of the devices actually picked for an order are returned by Order v2 - Getdetail.

Call it with the order_ids you received at order creation, or with your own customer_ref_ids:

curl --data "action=getdetail&client_id=YOUR_CLIENT_ID&nonce=NONCE&signature=SIGNATURE&customer_ref_ids=[\"MOUVEMENTREFERENCE12345678\"]" \
     'https://wbsapi.withings.net/v2/order'

Each product in the response carries a mac_addresses array listing the devices assigned to that order line:

{
  "status": 0,
  "body": {
    "orders": [
      {
        "order_id": "D12345678",
        "customer_ref_id": "MOUVEMENTREFERENCE12345678",
        "status": "SHIPPED",
        "ship_date": "2024-03-15",
        "products": [
          {
            "ean": "3700546702518",
            "quantity": 2,
            "mac_addresses": [
              "00:24:e4:xx:xx:xx",
              "00:24:e4:xx:xx:xx"
            ]
          }
        ]
      }
    ]
  }
}

note

mac_addresses is populated only once the order has shipped — the devices are assigned at picking, not at order creation. Wait for the order to reach status SHIPPED before reading the field. The carrier, carrier_service, tracking_number and parcel_status fields behave the same way.

Rather than polling, subscribe to order update notifications and call getdetail when you receive the shipment notification.

Persist these values against the member record in your own system as soon as the shipment is confirmed. Every later support case then starts from a serial number you already hold, rather than from a phone call asking a member to turn their scale over.

Next steps

Once you have the serial number, use it to diagnose the device: see Troubleshooting devices for the connectivity and data-flow checks.

tip

Two support articles cover this topic in end-user wording, and are safe to send to a program member directly: the Health Solutions article for pro devices, and the Withings support article for consumer devices, which also includes photos of each label location.