OKOK Scale

The OKOK Scale integrationIntegrations connect and integrate Home Assistant with your devices, services, and more. [Learn more] allows you to connect your OKOK·International App supported scale to Home Assistant. This lets you keep an eye on your weight over time in Home Assistant, chart it on a dashboard, and use each new measurement in your automations.

Use cases

• Track your weight over time with the history graph or a statistics graph on a dashboard, without depending on the OKOK cloud app.
• Get a notification with your weight after you step off the scale.
• Calculate derived values, such as your body mass index (BMI), with a template sensor.
• Trigger a morning routine, for example turning on the bathroom lights or starting the coffee machine, when you weigh yourself.

Supported devices

The following device is known to be supported by the integration:

• Tristar WG-2440

Other scales that work with the OKOK·International app are likely to work as well, as long as they broadcast their measurements in one of the supported data formats. See Known limitations.

Prerequisites

This integration requires a working Bluetooth setup, either a local Bluetooth adapter or an ESPHome Bluetooth proxy. The scale is battery-powered and only broadcasts while it is awake, so make sure it is awake by doing a measurement before adding it.

Configuration

To add the OKOK Scale device to your Home Assistant instance, use this My button:

Supported functionality

The OKOK Scale integrationIntegrations connect and integrate Home Assistant with your devices, services, and more. [Learn more] provides the following entitiesAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more].

Sensors

A scale exposes the following sensors:

• Weight: the measured weight. The unit follows the unit the scale is set to: kilograms or pounds. Measurements in stones and pounds are converted to pounds, and measurements in jin are converted to kilograms.
• Impedance: the measured body impedance in ohms (Ω), if supported by the scale. You need to stand on the scale barefoot for this to be measured.
• Battery: the scale battery percentage.
• Signal strength: the Bluetooth signal strength (diagnostic, disabled by default).

Examples

Send a notification with your weight

This automation sends a notification to your phone when the reported weight changes. It does not send a new notification if a measurement has the same value as the previous one. Replace sensor.okok_scale_2345_weight with the entity ID of your scale’s weight sensor, and notify.mobile_app_your_phone with your notification action.

To create this automation in the UI, go to Settings > Automations & scenes, select Create automation, and add:

• Trigger: Entity > State, with the weight sensor as the entity.
• Action: Notifications > Send a notification via mobile_app_your_phone, with a message that contains the weight.

alias: "Notify weight measurement"
triggers:
  - trigger: state
    entity_id: sensor.okok_scale_2345_weight
    not_from:
      - unknown
      - unavailable
    not_to:
      - unknown
      - unavailable
actions:
  - action: notify.mobile_app_your_phone
    data:
      title: "New measurement"
      message: >
        You weigh {{ trigger.to_state.state }}
        {{ trigger.to_state.attributes.unit_of_measurement }}.

Calculate your body mass index

This template sensor calculates your body mass index (BMI) from the weight sensor. Replace sensor.okok_scale_2345_weight with the entity ID of your scale’s weight sensor, and 1.80 with your height in meters. This example requires the weight sensor’s unit in Home Assistant to be set to kilograms.

To create this sensor in the UI, go to Settings > Devices & services > Helpers, select Create helper > Template > Template a sensor, and enter the template below as the State template.

{% set weight = states('sensor.okok_scale_2345_weight') | float(0) %}
{% set height = 1.80 %}
{{ (weight / (height ** 2)) | round(1) }}

23.1

Data updates

The scale broadcasts its measurements over Bluetooth while it is awake. The integration listens to these broadcasts (Local Push).

• Weight is read from the broadcasts. How often the sensor updates during a measurement depends on the data format of your scale. Some scales mark a measurement as final once the weight has stabilized, and the integration only updates the sensor with that final value. Other scales don’t mark measurements as final, so the sensor can update several times while the reading settles, ending with the final weight.
• Impedance is included in the broadcasts of some scales. Other scales only provide it over an active Bluetooth connection. When the integration detects that a scale provides impedance over a connection, it connects to the scale after each measurement to read it.
• Battery is read over an active Bluetooth connection: the first time the scale is seen after Home Assistant starts, after each measurement on scales that provide impedance over a connection, and otherwise at most once a day.

Between measurements the scale goes to sleep and stops broadcasting. The sensors then keep their last value instead of becoming unavailable, and are marked as having an assumed state.

Known limitations

Measurement availability

The scale only broadcasts for a short time while it is in use, so values are only updated when you use the scale. Depending on the data format of your scale, the weight sensor can show intermediate values while the reading settles.

Multiple users

Measurements are not linked to a person. If several people use the same scale, all measurements end up on the same weight sensor. You can use automations or template sensors to assign measurements to people, for example based on the weight range.

Body composition

The integration provides the raw impedance only. Body composition values such as body fat percentage are not calculated, because they depend on personal data such as height, age, and sex.

Bluetooth connections

Battery updates, and impedance updates on scales that do not broadcast impedance, need a Bluetooth adapter or proxy in range that supports active connections. With a passive-only adapter, weight and any impedance included in broadcasts can still update.

Battery reporting

Some scales always report a battery level of 0%.

Unsupported formats

Scales that broadcast using data format 10 or 26 are not supported yet.

Troubleshooting

Removing the integration

This integration follows standard integration removal. No extra steps are required.

To remove an integration instance from Home Assistant

1. Go to Settings > Devices & services and select the integration card.
2. Next to the entry you want to remove, select the three dots menu. Then, select Delete.
   • Depending on the integration, the entries are listed under one of the following headings:
     • Devices
     • Hubs
     • Services
     • Integration entries
3. To confirm, select Delete.
   • Home Assistant also deletes the devices and entities of the entry.
4. If Home Assistant asks you to restart, restart Home Assistant.
5. If Home Assistant asks whether to also delete the application credentials, select Remove or Keep.
   • If you keep them, Home Assistant uses them automatically when you add the integration again.
   • To delete them later, refer to Deleting application credentials.