Get a device name: device_name
The device_name template function returns the human-readable name of a deviceA device is a model representing a physical or logical unit that contains entities.. You can pass it 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. If a user-set name exists for the device, that name is returned; otherwise, the default device name is used. It returns None if no matching device is found.
This is useful whenever you want to display or include a device’s name in a notificationYou can use notifications to send messages, pictures, and more, to devices. [Learn more], dashboard card, or log message. For example, you could loop through all devices in an areaAn area in Home Assistant is a logical grouping of devices and entities that represents a room or space in your home, such as the living room, kitchen, or garage. [Learn more] and list their names, or include the device name in an alert so you know exactly which device reported a problem. Since it accepts both device IDs and entity IDs, you can use whichever you happen to have available.
Usage
Here’s how to use this template function. Copy any example and adjust it to your setup.
{{ device_name("a1b2c3d4e5f6a1b2c3d4e5f6") }}
Living Room Thermostat
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
-
roundis 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 as0or"unknown", not the wordAny. -
= 0and= "common"are default values. You can leave outprecisionandmethod, androunduses these default values. -
defaulthas no=, but the parameter list marksdefaultas optional. If you leave outdefaultandroundgets a value that isn’t a number,roundraises 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 asdefault.
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 as5 -
float: a decimal number, such as3.14 -
bool:trueorfalse -
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"} -
datetimeandtimedelta: 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:
-
*argsmeans 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 theroundexample, show this value as the first parameter between the parentheses instead.
device_name(
device_id_or_entity_id: str,
) -> str | None
Function parameters
The following parameters can be provided to this function.
Good to know
- Returns
Nonewhen no device matches the lookup value. - Uses the custom name if you set one, otherwise returns the default name the integration provided.
- Renaming a device updates the output immediately, so the result can change over time.
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 a device name from an entity ID
Pass an entity ID to find out the name of the device it belongs to.
{{ device_name("sensor.living_room_temperature") }}
Living Room Thermostat
Include device name in a notification
Send a notificationYou can use notifications to send messages, pictures, and more, to devices. [Learn more] that includes the name of the device reporting low battery.
action:
- action: notify.mobile
data:
message: >
{{ device_name("binary_sensor.front_door_battery") }}
has a low battery!
List all device names in an area
Combine with area_devices to display the names of all devices in an area.
{% for dev_id in area_devices("Kitchen") %}
{{ device_name(dev_id) }}
{% endfor %}
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.
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:
-
Get a device ID: device_id - Returns the device ID for a given entity ID or device name.
-
Get entities for a device: device_entities - Returns a list of entity IDs associated with a given device.
-
Get device attribute: device_attr - Returns the value of a specific attribute from a device.
-
Test device attribute: is_device_attr - Tests if a specific attribute of a device has a given value.