home-assistant.io/source/_components/sensor.template.markdown

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layout	title	description	date	sidebar	comments	sharing	footer	ha_category	ha_release	ha_iot_class	logo	ha_qa_scale
page	Template Sensor	Instructions on how to integrate Template Sensors into Home Assistant.	2016-01-27 07:00	true	false	true	true	Sensor	0.12	Local Push	home-assistant.png	internal

The template platform supports sensors which break out state_attributes from other entities.

If you do not supply an `entity_id` in the configuration you will need to run the service `homeassistant.update_entity` to update the sensor.

{% linkable_title Configuration %}

To enable Template Sensors in your installation, add the following to your configuration.yaml file:

{% raw %}

# Example configuration.yaml entry
sensor:
  - platform: template
    sensors:
      solar_angle:
        friendly_name: "Sun angle"
        unit_of_measurement: 'degrees'
        value_template: "{{ states.sun.sun.attributes.elevation }}"

      sunrise:
        value_template: "{{ states.sun.sun.attributes.next_rising }}"

{% endraw %}

{% configuration %} sensors: description: List of your sensors. required: true type: map keys: friendly_name: description: Name to use in the frontend. required: false type: string friendly_name_template: description: Defines a template for the name to be used in the frontend (this overrides friendly_name). required: false type: template entity_id: description: The template engine will attempt to work out what entities should trigger an update of the sensor. If this fails to get the correct list (for example if your template loops over the contents of a group) then you can provide a list of entity IDs that will cause the sensor to update. required: false type: string, list unit_of_measurement: description: "Defines the units of measurement of the sensor, if any. This will also influence the graphical presentation in the history visualisation as continuous value. Sensors with missing unit_of_measurement are showing as discrete values." required: false type: string default: None value_template: description: Defines a template to get the state of the sensor. required: true type: template icon_template: description: Defines a template for the icon of the sensor. required: false type: template entity_picture_template: description: Defines a template for the entity picture of the sensor. required: false type: template device_class: description: Sets the class of the device, changing the device state and icon that is displayed on the UI (see below). It does not set the unit_of_measurement. required: false type: device_class default: None {% endconfiguration %}

{% linkable_title Considerations %}

If you are using the state of a platform that takes extra time to load, the Template Sensor may get an unknown state during startup. To avoid this (and the resulting error messages in your log file), you can use is_state() function in your template. For example, you would replace {% raw %}{{ states.switch.source.state == 'on' }}{% endraw %} with this equivalent that returns true/false and never gives an unknown result: {% raw %}{{ is_state('switch.source', 'on') }}{% endraw %}

{% linkable_title Examples %}

In this section you find some real-life examples of how to use this sensor.

{% linkable_title Sun Angle %}

This example shows the sun angle in the frontend.

{% raw %}

sensor:
  - platform: template
    sensors:
      solar_angle:
        friendly_name: "Sun Angle"
        unit_of_measurement: '°'
        value_template: "{{ '%+.1f'|format(states.sun.sun.attributes.elevation) }}"

{% endraw %}

{% linkable_title Renaming Sensor Output %}

If you don't like the wording of a sensor output then the Template Sensor can help too. Let's rename the output of the Sun component as a simple example:

{% raw %}

sensor:
  - platform: template
    sensors:
      sun_state:
        friendly_name: "Sun State"
        value_template: >-
          {% if is_state('sun.sun', 'above_horizon') %}
            up
          {% else %}
            down
          {% endif %}

{% endraw %}

Processes monitored by the System Monitor sensor show on or off if they are running or not. This example shows how the output of a monitored glances process can be renamed.

{% raw %}

sensor:
  - platform: template
    sensors:
      glances:
        friendly_name: "Glances"
        value_template: >-
          {% if is_state('sensor.process_glances', 'on') %}
            running
          {% else %}
            not running
          {% endif %}

{% endraw %}

The Template Binary Sensor is the one in similar cases if you prefer to see an icon instead of text.

{% linkable_title Multiline Example With an if Test %}

This example shows a multiple line template with an if test. It looks at a sensing switch and shows on/off in the frontend.

{% raw %}

sensor:
  - platform: template
    sensors:
      kettle:
        friendly_name: "Kettle"
        value_template: >-
          {% if is_state('switch.kettle', 'off') %}
            off
          {% elif states.switch.kettle.attributes.kwh|float < 1000 %}
            standby
          {% elif is_state('switch.kettle', 'on') %}
            on
          {% else %}
            failed
          {% endif %}

      next_sensor:
        ...

{% endraw %}

{% linkable_title Change The Unit of Measurement %}

With a Template Sensor it's easy to convert given values into others if the unit of measurement doesn't fit your needs.

{% raw %}

sensor:
  - platform: template
    sensors:
      transmission_down_speed_kbps:
        friendly_name: "Transmission Down Speed"
        unit_of_measurement: 'kB/s'
        value_template: "{{ states('sensor.transmission_down_speed')|float * 1024 }}"

      transmission_up_speed_kbps:
        friendly_name: "Transmission Up Speed"
        unit_of_measurement: 'kB/s'
        value_template: "{{ states('sensor.transmission_up_speed')|float * 1024 }}"

{% endraw %}

{% linkable_title Change The Icon %}

This example shows how to change the icon based on the day/night cycle.

{% raw %}

sensor:
  - platform: template
    sensors:
      day_night:
        friendly_name: "Day/Night"
        value_template: >-
          {% if is_state('sun.sun', 'above_horizon') %}
            Day
          {% else %}
            Night
          {% endif %}
        icon_template: >-
          {% if is_state('sun.sun', 'above_horizon') %}
            mdi:weather-sunny
          {% else %}
            mdi:weather-night
          {% endif %}

{% endraw %}

{% linkable_title Change The Entity Picture %}

This example shows how to change the entity picture based on the day/night cycle.

{% raw %}

sensor:
  - platform: template
    sensors:
      day_night:
        friendly_name: "Day/Night"
        value_template: >-
          {% if is_state('sun.sun', 'above_horizon') %}
            Day
          {% else %}
            Night
          {% endif %}
        entity_picture_template: >-
          {% if is_state('sun.sun', 'above_horizon') %}
            /local/daytime.png
          {% else %}
            /local/nighttime.png
          {% endif %}

{% endraw %}

{% linkable_title Change the Friendly Name Used in the Frontend %}

This example shows how to change the friendly_name based on a date. Explanation: We add a multiple of 86400 seconds (= 1 day) to the current unix timestamp to get a future date.

{% raw %}

sensor:
  - platform: template
    sensors:
      forecast_1_day_ahead:
        friendly_name_template: >-
          {%- set date = as_timestamp(now()) + (1 * 86400 ) -%}
          {{ date|timestamp_custom("Tomorrow (%-m/%-d)") }}
        value_template: "{{ sensor.darksky_weather_forecast_1 }}"
      forecast_2_days_ahead:
        friendly_name_template: >-
          {%- set date = as_timestamp(now()) + (2 * 86400 ) -%}
          {{ date|timestamp_custom("%A (%-m/%-d)") }}
        value_template: "{{ sensor.darksky_weather_forecast_2 }}"

{% endraw %}

This example shows how to change the friendly_name based on a state.

{% raw %}

sensor:
  - platform: template
    sensors:
      net_power:
        friendly_name_template: >-
          {% if states('sensor.power_consumption')|float < 0 %}
            Power Consumption
          {% else %}
            Power Production
          {% end %}
        value_template: "{{ states('sensor.power_consumption') }}"
        unit_of_measurement: 'kW'

{% endraw %}

{% linkable_title Working with dates %}

The template sensors are not limited to use attributes from other entities but can also work with Home Assistant's template extensions. This template contains no entities that will trigger an update, so either we need to use homeassistant.update_entity or add an entity_id: line for an entity that will force an update - here we're using sensor.date.

{% raw %}

sensor:
- platform: template
  sensors:
    nonsmoker:
      value_template: '{{ (( as_timestamp(now()) - as_timestamp(strptime("06.07.2018", "%d.%m.%Y")) ) / 86400 ) | round(2) }}'
      entity_id: sensor.date
      friendly_name: 'Not smoking'
      unit_of_measurement: "Days"

{% endraw %}

Useful entities to choose might be sensor.date which update once per day, or sensor.time which updates once per minute.

Note: If a template uses more than one sensor they can be listed

The alternative to this is to create an Automationusing the new (81.0) service homeassistant.update_entity and list all entity's requiring updates and setting the interval based on time.

{% raw %}

automation:
  - alias: 'nonsmoker_update'
    trigger:
      - platform: time
        minutes: '/1'
    action:
      - service: homeassistant.update_entity
        entity_id: sensor.nonsmoker

{% endraw %}