2026.10.4
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Get device attribute: device_attr

The device_attr template function returns the value of a specific attribute from a deviceA device is a model representing a physical or logical unit that contains entities. in the device registry. You can pass either a device ID or an entityAn 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] ID along with the attribute name you want to retrieve. If the device or attribute doesn’t exist, it returns None.

This is useful when you need device-level information that isn’t available through entity states or attributes. For example, you might want to check the manufacturer, model, software version, or serial number of a device. You could use this to track which devices need firmware updates, build a hardware inventory, or include model information in a support request notification. Common attribute names include manufacturer, model, sw_version, hw_version, serial_number, and identifiers.

Usage

Here’s how to use this template function. Copy any example and adjust it to your setup.

TemplateA template is an automation definition that can include variables for the action or data from the trigger values. This allows automations to generate dynamic actions. [Learn more] 
{{ device_attr("a1b2c3d4e5f6a1b2c3d4e5f6", "manufacturer") }}
Result (stringA piece of text, like a name, message, or entity ID. In templates, wrap strings in quotes, like "living_room" or "lights are on".) 
Philips

Function signature

The signature is a technical summary of this template function. It shows the name of the function, the values (called parameters) it accepts, and what type of data each parameter expects (for example, a piece of text or a number).

Function parameters that have a = with a value after them are optional. If you leave them out, the default value shown is used automatically.

Function parameters without a = are usually required. A few optional parameters have no default value, so the signature shows them without a = as well. To check whether a parameter is required, look at the parameter list below the signature. Each parameter is marked as Required or Optional.

The most common optional parameter without a default value is default. The default parameter sets the value a function returns when the function can’t produce a result, for example, when float gets text that isn’t a number. If you leave out default, there is no fallback value, so most functions raise an error and the template fails. The parameter list of each function says what happens. If you set default, the function returns your value instead.

How to read a signature

Here is the signature of the round filter as an example:

round(
    value: Any,
    precision: int = 0,
    method: str = "common",
    default: Any,
) -> float | int | Any
  • round is the name of the function.
  • Between the parentheses are the parameters. Each parameter has a name, followed by a colon and the type of value the parameter expects. The type only tells you what kind of value to pass. For default: Any, you pass a value of any type, such as 0 or "unknown", not the word Any.
  • = 0 and = "common" are default values. You can leave out precision and method, and round uses these default values.
  • default has no =, but the parameter list marks default as optional. If you leave out default and round gets a value that isn’t a number, round raises an error.
  • -> shows the type of value the function returns.
  • Inside a signature, | means “or”. This function returns a decimal number, a whole number, or the value you passed as default.

round is a filter, so the first parameter, value, is the value before the |. For example, {{ 3.14159 | round(2) }} returns 3.14.

The types you’ll see most often:

  • str: text, such as "hello"
  • int: a whole number, such as 5
  • float: a decimal number, such as 3.14
  • bool: true or false
  • list: a list of values, such as [1, 2, 3]. list[str] is a list of texts.
  • dict: a set of keys and values, such as {"name": "Kitchen"}
  • datetime and timedelta: a date and time, and a duration. For details, refer to Dates and times.
  • None: no value
  • Any: any type of value

Some signatures use special forms:

  • *args means you can pass any number of values, separated by commas. For example, average(1, 2, 3).
  • value | name(...) means the function is a filter. The value before the | is passed to the filter as its first parameter. Some filter signatures, like the round example, show this value as the first parameter between the parentheses instead.
device_attr(
    device_or_entity_id: str,
    attr_name: str,
) -> Any

Function parameters

The following parameters can be provided to this function.

device_or_entity_id string Required

The device ID or entity ID to look up. When using an entity ID, the function first resolves the device the entity belongs to.

attr_name string Required

The name of the device attribute to retrieve. Common attributes include manufacturer, model, sw_version, hw_version, serial_number, and identifiers.

Tip

Device attributes are stored in the device registry and are separate from entity state attributes. You can view commonly used device information, such as the manufacturer, model, software version, hardware version, and serial number, by going to Settings > Devices & services, selecting Devices, and then selecting a device. Not every device registry attribute is shown in the user interface.

Good to know

  • Returns None when the device or attribute does not exist, so chain with | default(value) for display fallbacks.
  • The device or entity ID must be text. If it’s None, the template fails with the error Must provide a device or entity ID. This can happen when you nest two calls, such as device_attr(device_attr(device_id, "via_device_id"), "name"). If the inner call returns None, the outer call fails.
  • This reads from the device registry, not the entity state. Attributes like manufacturer and sw_version live here, not in state_attr.
  • Accepts either a device ID or an entity ID. When given an entity ID, it resolves to the device first.

Try it yourself

Ready to test this? Open Settings > Tools > Template, paste the example into the Template editor, and watch the result update on the right. Edit the values to see how the function adapts to your own 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].

More examples

Real scenarios where this function comes up in automations and templates. Copy any example and adapt it to your setup.

Get the model of a device from an entity ID

You can pass an entity ID directly. The function automatically resolves the device behind the entity.

TemplateA template is an automation definition that can include variables for the action or data from the trigger values. This allows automations to generate dynamic actions. [Learn more] 
{{ device_attr("light.living_room", "model") }}
Result (stringA piece of text, like a name, message, or entity ID. In templates, wrap strings in quotes, like "living_room" or "lights are on".) 
LCA001

Check the firmware version of a device

Read the software version to see if a device is up to date.

TemplateA template is an automation definition that can include variables for the action or data from the trigger values. This allows automations to generate dynamic actions. [Learn more] 
{{ device_attr("a1b2c3d4e5f6a1b2c3d4e5f6", "sw_version") }}
Result (stringA piece of text, like a name, message, or entity ID. In templates, wrap strings in quotes, like "living_room" or "lights are on".) 
1.104.2

Include device info in a notification

Send a notificationYou can use notifications to send messages, pictures, and more, to devices. [Learn more] with the manufacturer and model when a device goes offline.

ActionAn action makes Home Assistant do something, for example, turn on a light, send a notification, or activate a scene. Automations and scripts run a list of actions. [Learn more] 
action:
  - action: notify.mobile
    data:
      message: >
        {{ device_name("sensor.garage_door_battery") }} is offline.
        Device:
        {{ device_attr("sensor.garage_door_battery", "manufacturer") }}
        {{ device_attr("sensor.garage_door_battery", "model") }}

Still stuck?

The Home Assistant community is quick to help: join Discord for real-time chat, post on the community forum with your template and expected result, or share on our subreddit /r/homeassistant.

Tip

AI assistants like ChatGPT or Claude can also explain or fix templates when you describe what you want in plain language.

Related template functions

These functions work well alongside this one: