---
title: Binary sensor
description: Instructions on how-to setup binary sensors with Home Assistant.
ha_category:
  - Binary sensor
ha_release: 0.9
ha_quality_scale: internal
ha_domain: binary_sensor
ha_codeowners:
  - '@home-assistant/core'
ha_integration_type: entity
---

Binary sensors are similar to other [sensors](/integrations/sensor) in that they
monitor the states and conditions of different entities. Where binary sensors
differ is they can only return one of two mutually exclusive values.
For example, a binary sensor for a window may report a value
of `open` or `closed`, a switch `on` or `off`, a condition `true` or `false`.

This *either/or* constraint is what makes these sensors binary. They are digital
in nature, whereas analog sensors, like temperature and weight sensors,
return a range of values.

Some binary sensors are created automatically when you add a device integration.
For example, adding the [ecobee integration](/integrations/ecobee/) will create
a binary sensor to detect room occupancy. Other binary sensors can be created
manually using the [template integration](/integrations/template/)
or using an [input boolean helper](/integrations/input_boolean).

{% include integrations/building_block_integration.md %}

## The state of binary sensor

A binary sensor can have two states: **on** or **off**. However, in the frontend, they might not be called **on** or **off**, but use an alternative term to be more meaningful in context. For example, hot/cold, locked/unlocked. The meaning of an **on** or **off** state depends on the device class.

In addition, the entity can have the following states:

- **Unavailable**: The entity is currently unavailable.
- **Unknown**: The state is not yet known.

### Device class

{% include integrations/device_class_intro.md %}

The screenshot shows a few examples of different device classes for binary sensors:

![List of binary sensors](/images/screenshots/binary_sensor_classes_icons.png)

Example of various device classes icons in `on` and `off` state. The on image
in this example has `state_color: true` specified in the entities card
configuration to receive the icon coloring.

The following device classes are supported for binary sensors:

- **None**: Generic on/off. This is the default and doesn't need to be set.
- **battery**: `on` means low, `off` means normal
- **battery_charging**: `on` means charging, `off` means not charging
- **carbon_monoxide**: `on` means carbon monoxide detected, `off` no carbon monoxide (clear)
- **cold**: `on` means cold, `off` means normal
- **connectivity**: `on` means connected, `off` means disconnected
- **door**: `on` means open, `off` means closed
- **garage_door**: `on` means open, `off` means closed
- **gas**: `on` means gas detected, `off` means no gas (clear)
- **heat**: `on` means hot, `off` means normal
- **light**: `on` means light detected, `off` means no light
- **lock**: `on` means open (unlocked), `off` means closed (locked)
- **moisture**: `on` means moisture detected (wet), `off` means no moisture (dry)
- **motion**: `on` means motion detected, `off` means no motion (clear)
- **moving**: `on` means moving, `off` means not moving (stopped)
- **occupancy**: `on` means occupied (detected), `off` means not occupied (clear)
- **opening**: `on` means open, `off` means closed
- **plug**: `on` means device is plugged in, `off` means device is unplugged
- **power**: `on` means power detected, `off` means no power
- **presence**: `on` means home, `off` means away
- **problem**: `on` means problem detected, `off` means no problem (OK)
- **running**: `on` means running, `off` means not running
- **safety**: `on` means unsafe, `off` means safe
- **smoke**: `on` means smoke detected, `off` means no smoke (clear)
- **sound**: `on` means sound detected, `off` means no sound (clear)
- **tamper**: `on` means tampering detected, `off` means no tampering (clear)
- **update**: `on` means update available, `off` means up-to-date
- **vibration**: `on` means vibration detected, `off` means no vibration (clear)
- **window**: `on` means open, `off` means closed

For comparison, here are the [device classes](https://www.home-assistant.io/integrations/sensor#device-class) for analog sensors.