Convert to lowercase: lower

The lower filter converts all characters in a string to lowercase. This is useful when you need to normalize text for comparison or display. For example, sensorSensors return information about a thing, for instance the level of water in a tank. [Learn more] states may come in mixed case like On or OFF, and converting to lowercase lets you compare them consistently. It is also handy for formatting text before using it in entity IDs or other contexts that expect lowercase values.

Usage

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

{{ "Hello WORLD" | lower }}

hello world

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 default are required.

lower(
    value: str,
) -> str

Function parameters

The following parameters can be provided to this function.

Good to know

• Entity states in Home Assistant are already lowercase (for example, on, off, heating), so this filter is most useful for attributes, user input, or text from external sources.
• Non-letter characters like digits and punctuation pass through unchanged.

Try it yourself

Ready to test this? Open Developer 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.

Normalize a state for comparison

Convert a sensor state to lowercase so comparisons work regardless of how the value is capitalized.

{% if states("sensor.status") | lower == "online" %}
  Device is online
{% else %}
  Device is offline
{% endif %}

Device is online

Format text for display

Ensure a label is consistently lowercase for a clean look on a dashboard.

{{ "MOTION DETECTED" | lower }}

motion detected

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:

• Convert to uppercase: upper - Converts all characters in a string to uppercase.

• Capitalize first character: capitalize - Capitalizes the first character of a string and lowercases the rest.

• Convert to title case: title - Converts a string to title case, capitalizing the first letter of each word.