Template Sensor

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

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

# 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 }}"

Configuration Variables

sensors

(map)(Required)List of your sensors.

friendly_name: (string)(Optional)Name to use in the frontend.
entity_id: (string | list)(Optional)Add a list of entity IDs so the sensor only reacts to state changes of these entities. This will reduce the number of times the sensor will try to update its state.
unit_of_measurement: (string)(Optional)Defines the units of measurement of the sensor, if any.
value_template: (template)(Required)Defines a template to get the state of the sensor.
icon_template: (template)(Optional)Defines a template for the icon of the sensor.

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. This results in error messages in your log file until that platform has completed loading. If you use is_state() function in your template, you can avoid this situation. For example, you would replace {{ states.switch.source.state == 'on' }} with this equivalent that returns true/false and never gives an unknown result: {{ is_state('switch.source', 'on') }}

Examples

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

Sun Angle

This example shows the sun angle in the frontend.

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

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:

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

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.

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

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

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.

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:
        ...

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.

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 }}"

Change The Icon

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

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 %}