2026.10.4
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Calculate distance: distance

The distance template function calculates the straight-line distance between two locations. If you only provide one location, it calculates the distance from your home to that point. Locations can be specified as 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] IDs (for entities with GPS coordinates, such as a zone or a person), state objects, or latitude/longitude pairs.

This is useful for proximity-based automationsAutomations in Home Assistant allow you to automatically respond to things that happen in and around your home. [Learn more]. You could send a notificationYou can use notifications to send messages, pictures, and more, to devices. [Learn more] when someone is within a certain distance of home, check how far apart family members are, or determine how far away an entity is from a specific zone. The result is a number, in kilometers or miles depending on your unit system, that you can use in conditionsConditions check whether something is true at that moment, for example, whether a door is closed. You can use them in automations and scripts. If a condition is not met, the actions that come after it in the same sequence do not run. At the top level of an automation or script, this stops the automation or script. [Learn more] and comparisons.

Usage

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

As a function 
{{ distance("device_tracker.phone") }}
Result (floatA number that can have decimal places, like 21.5 or 3.14. Used for temperatures, percentages, and other measurements that need precision.) 
5.2

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.
distance(
    *args: str | State | float,
) -> float | None

Function parameters

The following parameters can be provided to this function.

args any Required

One or two locations. A location is either an entity ID with GPS data (such as zone.work), a state object, or two numbers in a row for latitude and longitude. A zone name such as "Work" doesn’t work, because text that isn’t an entity ID is read as a latitude. Examples of valid calls: distance("device_tracker.phone") (distance from home to the entity), distance(52.5, 13.4) (distance from home to a lat/lon point), distance("device_tracker.a", "device_tracker.b") (distance between two entities), distance("device_tracker.phone", 52.5, 13.4) (distance between an entity and a lat/lon point).

Good to know

  • Returns None when any location lacks GPS coordinates, so guard your comparisons for missing data.
  • The result uses the length unit of your unit system: kilometers for metric, and miles for US customary. To check your unit system, go to Settings > System > General.
  • With a single location argument, distance is measured from your Home Assistant home location.

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.

Distance from home

Calculate how far a device tracker is from home.

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] 
{{ distance("device_tracker.phone") | round(1) }}
Result (floatA number that can have decimal places, like 21.5 or 3.14. Used for temperatures, percentages, and other measurements that need precision.) 
5.2

Distance between two entities

Calculate the distance between two people.

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] 
{{
  distance("device_tracker.phone_a",
  "device_tracker.phone_b") | round(1)
}}
Result (floatA number that can have decimal places, like 21.5 or 3.14. Used for temperatures, percentages, and other measurements that need precision.) 
12.7

Distance using coordinates

Calculate the distance from home to a specific latitude/longitude.

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] 
{{ distance(52.5, 13.4) | round(1) }}
Result (floatA number that can have decimal places, like 21.5 or 3.14. Used for temperatures, percentages, and other measurements that need precision.) 
847.3

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: