Bitwise AND: bitwise_and

The bitwise_and template function performs a bitwise AND operation on two integer values. Each bit in the result is set to 1 only if both corresponding bits in the input values are 1.

This is useful when working with devicesA device is a model representing a physical or logical unit that contains entities. that communicate status or configuration using bitmasks. For example, some sensorsSensors return information about a thing, for instance the level of water in a tank. [Learn more] report multiple flags packed into a single integer value, and you can use bitwise_and to check whether a specific flag bit is set. It is also helpful for masking out specific bits from a register value.

Usage

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

{{ bitwise_and(7, 3) }}

3

{{ 7 | bitwise_and(3) }}

3

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.

bitwise_and(
    first_value: Any,
    second_value: Any,
) -> int

Function parameters

The following parameters can be provided to this function.

Good to know

• Both inputs must be integers. Convert state strings with int first.
• To test whether a specific bit is set, compare the result to the bit mask or to zero.

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.

Checking a status bit

Check if bit 2 (value 4) is set in a sensor’s status register.

{% set status = states("sensor.device_status") | int %}
{{ bitwise_and(status, 4) > 0 }}

True

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:

• Bitwise OR: bitwise_or - Performs a bitwise OR operation on two values.

• Bitwise XOR: bitwise_xor - Performs a bitwise XOR (exclusive OR) operation on two values.