2026.5.4
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Illuminance

This integrationIntegrations connect and integrate Home Assistant with your devices, services, and more. [Learn more] provides automation triggers and conditions for binary sensors with device class light and for sensor and number entities with device class illuminance. There are no configuration options for this integration.

Illuminance and brightness

  • Illuminance is a measured input. It describes how much ambient light is reaching a sensor and is reported in lux (lx) by entities like a room or outdoor light sensor. You react to it with the triggers and conditions in this integration.
  • Brightness is a controllable output. It is a property of light entities in the Light integration, expressed as a value between 0 and 255, or as a percentage in the UI. You set it when turning a lamp on, for example with the Turn on light action and setting Brightness to 40%.

A common pattern is to combine them: use an Illuminance crossed threshold trigger to react when ambient light drops, then use the Light integration’s Turn on light action to set the lamps to the brightness level you want.

List of triggers

The Illuminance integrationIntegrations connect and integrate Home Assistant with your devices, services, and more. [Learn more] provides the following triggers. Each link below opens a dedicated page with examples, fields, and a step-by-step UI walkthrough.

  • Illuminance changed (illuminance.changed) Triggers after one or more illuminance values change.

  • Light cleared (illuminance.cleared) Triggers after one or more light sensors stop detecting light.

  • Illuminance crossed threshold (illuminance.crossed_threshold) Triggers after one or more illuminance values cross a threshold.

  • Light detected (illuminance.detected) Triggers after one or more light sensors start detecting light.

For an overview of every trigger across all integrations, see the triggers reference.

List of conditions

The Illuminance integrationIntegrations connect and integrate Home Assistant with your devices, services, and more. [Learn more] provides the following conditions. Each link below opens a dedicated page with examples, fields, and a step-by-step UI walkthrough.

  • Light is detected (illuminance.is_detected) Tests if light is currently detected.

  • Light is not detected (illuminance.is_not_detected) Tests if light is currently not detected.

  • Illuminance (illuminance.is_value) Tests if an illuminance value is above a threshold, below a threshold, or in a range of values.

For an overview of every condition across all integrations, see the conditions reference.