Template

The template integration allows creating entities which derive their values from other data. This is done by specifying templates for properties of an entity, like the name or the state.

Sensors, binary (on/off) sensors, numbers and selects are covered on this page. For other types, please see the specific pages:

• Alarm Control Panel
• Cover
• Fan
• Light
• Lock
• Switch
• Vacuum
• Weather

Sensor, binary sensor, number and select template entities are defined in your YAML configuration files, directly under the template: key and cannot be configured via the UI. You can define multiple configuration blocks as a list. Each block defines sensor/binary sensor/number/select entities and can contain an optional update trigger.

For old sensor/binary sensor configuration format, see below.

State-based template sensors

Template entities will by default update as soon as any of the referenced data in the template updates.

For example, you can have a template that takes the averages of two sensors. Home Assistant will update your template sensor as soon as either source sensor updates.

template:
  - sensor:
      - name: "Average temperature"
        unit_of_measurement: "°C"
        state: >
          {% set bedroom = states('sensor.bedroom_temperature') | float %}
          {% set kitchen = states('sensor.kitchen_temperature') | float %}

          {{ ((bedroom + kitchen) / 2) | round(1, default=0) }}

Trigger-based template sensors

If you want more control over when an entity updates, you can define a trigger. Triggers follow the same format and work exactly the same as triggers in automations. This feature is a great way to create entities based on webhook data (example), or update entities based on a schedule.

Whenever the trigger fires, all related entities will re-render and it will have access to the trigger data in the templates.

Trigger-based entities do not automatically update when states referenced in the templates change. This functionality can be added back by defining a state trigger for each entity that you want to trigger updates.

# Example configuration entry
template:
  - trigger:
      - platform: time_pattern
        # This will update every night
        hours: 0
        minutes: 0
    sensor:
      # Keep track how many days have past since a date
      - name: "Not smoking"
        state: '{{ ( ( as_timestamp(now()) - as_timestamp(strptime("06.07.2018", "%d.%m.%Y")) ) / 86400 ) | round(default=0) }}'
        unit_of_measurement: "Days"

The above configuration variables describe a configuration section. The template integration allows defining multiple sections.

# Example configuration.yaml entry with two sections
template:
  # Define state-based template entities
  - sensor:
      ...
  - binary_sensor:
      ...

  # Define trigger-based template entities
  - trigger:
      ...
    sensor:
      ...
    binary_sensor:
      ...

Rate limiting updates

When there are entities present in the template and no triggers are defined, the template will be re-rendered when one of the entities changes states. To avoid this taking up too many resources in Home Assistant, rate limiting will be automatically applied if too many states are observed.

Define a trigger to avoid a rate limit and get more control over entity updates.

When states is used in a template by itself to iterate all states on the system, the template is re-rendered each time any state changed event happens if any part of the state is accessed. When merely counting states, the template is only re-rendered when a state is added or removed from the system. On busy systems with many entities or hundreds of thousands state changed events per day, templates may re-render more than desirable.

In the below example, re-renders are limited to once per minute because we iterate over all available entities:

template:
  - binary_sensor:
      - name: "Has Unavailable States"
        state: "{{ states | selectattr('state', 'in', ['unavailable', 'unknown', 'none']) | list | count }}"

In the below example, re-renders are limited to once per second because we iterate over all entities in a single domain (sensor):

template:
  - binary_sensor:
      - name: "Has Unavailable States"
        state: "{{ states.sensor | selectattr('state', 'in', ['unavailable', 'unknown', 'none']) | list | count }}"

If the template accesses every state on the system, a rate limit of one update per minute is applied. If the template accesses all states under a specific domain, a rate limit of one update per second is applied. If the template only accesses specific states, receives update events for specifically referenced entities, or the homeassistant.update_entity service is used, no rate limit is applied.

Considerations

Startup

If you are using the state of a platform that might not be available during startup, the Template Sensor may get an unknown state. To avoid this, use is_state() function in your template. 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.

Storing webhook information

Template entities can be triggered using any automation trigger, including webhook triggers. Use a trigger-based template entity to store this information in template entities.

template:
  - trigger:
      - platform: webhook
        webhook_id: my-super-secret-webhook-id
    sensor:
      - name: "Webhook Temperature"
        state: "{{ trigger.json.temperature }}"
        unit_of_measurement: °C

      - name: "Webhook Humidity"
        state: "{{ trigger.json.humidity }}"
        unit_of_measurement: %

    binary_sensor:
      - name: "Motion"
        state: "{{ trigger.json.motion }}"
        device_class: motion

You can test this trigger entity with the following CURL command:

curl --header "Content-Type: application/json" \
  --request POST \
  --data '{"temperature": 5, "humidity": 34, "motion": true}' \
  http://homeassistant.local:8123/api/webhook/my-super-secret-webhook-id

Turning an event into a binary sensor

You can use a trigger-based template entity to convert any event or other automation trigger into a binary sensor. The below configuration will turn on a binary sensor for 5 seconds when the automation trigger triggers.

template:
  trigger:
    platform: event
    event_type: my_event
  binary_sensor:
    - name: Event recently fired
      auto_off: 5
      state: "true"

Sun Angle

This example shows the sun angle in the frontend.

template:
  - sensor:
      - name: Sun Angle
        unit_of_measurement: "°"
        state: "{{ '%+.1f'|format(state_attr('sun.sun', '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:

template:
  - sensor:
      - name: "Sun State"
        state: >
          {% if is_state('sun.sun', 'above_horizon') %}
            up
          {% else %}
            down
          {% endif %}

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, and shows ‘standby’ if the power use is less than 1000 watts.

template:
  - sensor:
      - name: "Kettle"
        state: >
          {% if is_state('switch.kettle', 'off') %}
            off
          {% elif state_attr('switch.kettle', 'W')|float < 1000 %}
            standby
          {% elif is_state('switch.kettle', 'on') %}
            on
          {% else %}
            failed
          {% endif %}

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.

template:
  - sensor:
      - name: "Transmission Down Speed"
        unit_of_measurement: "kB/s"
        state: "{{ states('sensor.transmission_down_speed')|float * 1024 }}"

      - name: "Transmission Up Speed"
        unit_of_measurement: "kB/s"
        state: "{{ states('sensor.transmission_up_speed')|float * 1024 }}"

Washing Machine Running

This example creates a washing machine “load running” sensor by monitoring an energy meter connected to the washer. During the washer’s operation, the energy meter will fluctuate wildly, hitting zero frequently even before the load is finished. By utilizing delay_off, we can have this sensor only turn off if there has been no washer activity for 5 minutes.

# Determine when the washing machine has a load running.
template:
  - binary_sensor:
      - name: "Washing Machine"
        delay_off:
          minutes: 5
        state: >
          {{ states('sensor.washing_machine_power')|float > 0 }}

Is Anyone Home

This example is determining if anyone is home based on the combination of device tracking and motion sensors. It’s extremely useful if you have kids/baby sitter/grand parents who might still be in your house that aren’t represented by a trackable device in Home Assistant. This is providing a composite of Wi-Fi based device tracking and Z-Wave multisensor presence sensors.

template:
  - binary_sensor:
      - name: People home
        state: >
          {{ is_state('device_tracker.sean', 'home')
             or is_state('device_tracker.susan', 'home')
             or is_state('binary_sensor.office_124', 'on')
             or is_state('binary_sensor.hallway_134', 'on')
             or is_state('binary_sensor.living_room_139', 'on')
             or is_state('binary_sensor.porch_ms6_1_129', 'on')
             or is_state('binary_sensor.family_room_144', 'on') }}

Device Tracker sensor with Latitude and Longitude Attributes

This example shows how to combine a non-GPS (e.g., NMAP) and GPS device tracker while still including latitude and longitude attributes

template:
  - binary_sensor:
      - name: My Device
        state: >
          {{ is_state('device_tracker.my_device_nmap', 'home') or is_state('device_tracker.my_device_gps', 'home') }}
        device_class: "presence"
        attributes:
          latitude: >
            {% if is_state('device_tracker.my_device_nmap', 'home') %}
              {{ state_attr('zone.home', 'latitude') }}
            {% else %}
              {{ state_attr('device_tracker.my_device_gps', 'latitude') }}
            {% endif %}
          longitude: >
            {% if is_state('device_tracker.my_device_nmap', 'home') %}
              {{ state_attr('zone.home', 'longitude') }}
            {% else %}
              {{ state_attr('device_tracker.my_device_gps', 'longitude') }}
            {% endif %}

Change the icon when a state changes

This example demonstrates how to use template to change the icon as its state changes. This icon is referencing its own state.

template:
  - binary_sensor:
      - name: Sun Up
        state: >
          {{ is_state("sun.sun", "above_horizon") }}
        icon: >
          {% if is_state("binary_sensor.sun_up", "on") %}
            mdi:weather-sunset-up
          {% else %}
            mdi:weather-sunset-down
          {% endif %}

Legacy binary sensor configuration format

This format still works but is no longer recommended. Use modern configuration.

This format is configured as a platform for the binary_sensor integration and not directly under the template integration.

# Example configuration.yaml entry
binary_sensor:
  - platform: template
    sensors:
      sun_up:
        friendly_name: "Sun is up"
        value_template: {{ state_attr('sun.sun', 'elevation') > 0 }}

Legacy Sensor configuration format

This format still works but is no longer recommended. Use modern configuration.

This format is configured as a platform for the sensor integration and not directly under the template integration.

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

      sunrise:
        value_template: "{{ state_attr('sun.sun', 'next_rising') }}"

Event event_template_reloaded

Event event_template_reloaded is fired when Template entities have been reloaded and entities thus might have changed.

This event has no additional data.