Cycle through values: cycler

The cycler template function creates an object that cycles through a sequence of values. You initialize it with the values you want to cycle through, then call .next() each iteration to advance to the next value. The .current property holds the current value, and the .reset() method returns to the beginning.

This can be handy when you need to alternate between values in a loop. For example, you could alternate between two labels, rotate through a set of icons, or cycle through status indicators. While less commonly used in typical Home Assistant templates, it can simplify patterns where you need repeating sequences.

Usage

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

{% set cycle = cycler("odd", "even") %}
{% for i in range(4) %}
  {{ cycle.next() }}
{% endfor %}

odd
even
odd
even

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.

round(
    value: Any,
    precision: int = 0,
    method: str = "common",
    default: Any,
) -> float | int | Any

cycler(
    *items: Any,
) -> Cycler

Function parameters

The following parameters can be provided to this function.

Good to know

• Needs at least two values. Calling it with one item or none raises an error.
• .current peeks at the current value without advancing; .next() moves to the next one.
• The cycler is tied to the template run. A fresh call to the template starts from the first value again.

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.

Alternate labels in a list

Cycle through labels while iterating over items.

{% set priority = cycler("high", "medium", "low") %}
{% set rooms = ["Living Room", "Kitchen", "Bedroom"] %}
{% for room in rooms %}
  {{ room }}: {{ priority.next() }}
{% endfor %}

Living Room: high
Kitchen: medium
Bedroom: low

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.

Related template functions

These functions work well alongside this one:

• Generate a number sequence: range - Generates a sequence of numbers, like Python’s range(). Commonly used for looping a specific number of times.

• Join loop iterations: joiner - Creates a helper that joins loop iterations with a separator, returning an empty string on the first call.