Test if string: string

The string test checks whether a value is a string. It returns true if the value is of string type and false for any other type, including numbers and booleans.

In Home Assistant, 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] states are always strings, but attributes can be various types including numbers, booleans, and lists. This test is useful when you need to verify that a value is a string before performing string operations like splitting, replacing, or pattern matching.

Usage

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

{% if "hello" is string %}
  It is a string
{% endif %}

It is a string

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.

string(
    value: Any,
) -> bool

Function parameters

The following parameters can be provided to this test.

Good to know

• A numeric-looking string such as "42" still passes this test. The test looks at the type, not the content.
• All entity states are strings in Home Assistant, so this test is most useful for attributes or values built inside a template.

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.

Distinguish strings from numbers

Check whether a value is a string or a numeric type.

{{ "hello" is string }}
{{ 42 is string }}
{{ "42" is string }}

true
false
true

Conditionally process based on type

Handle an attribute differently depending on whether it is a string or another type.

{% set val = state_attr("sensor.device", "info") %}
{% if val is string %}
  Info: {{ val }}
{% else %}
  Info: {{ val | tojson }}
{% endif %}

Info: Ready

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 string: string - Converts a value to its string representation.

• Get the type of a value: typeof - Returns the type name of a value as a string.