# characteristicType The type of the characteristic. ``` var characteristicType: String { get } ``` ## Discussion A characteristic’s [`characteristicType`](/documentation/HomeKit/HMCharacteristic/characteristicType) is a string constant that tells you what the characteristic’s [`value`](/documentation/HomeKit/HMCharacteristic/value) represents. For example, if you detect a characteristic type of [`HMCharacteristicTypeCurrentTemperature`](/documentation/HomeKit/HMCharacteristicTypeCurrentTemperature), then you know that the corresponding [`value`](/documentation/HomeKit/HMCharacteristic/value) is a measure of the current temperature. ```swift if characteristic.characteristicType == HMCharacteristicTypeCurrentTemperature, let temperatureValue = (characteristic.value as? NSNumber)?.floatValue { let temperature = String(format: "%.1f", temperatureValue) print("The current temperature is \(temperature) °C") } ``` From the type, you can typically infer the value’s format. The value for the current temperature is always a floating point number measured in degrees Celsius, as shown in the code snippet above. You can also use the characteristic’s [`metadata`](/documentation/HomeKit/HMCharacteristic/metadata) to get explicit and detailed guidance on how to format the value. See [Characteristic types](/documentation/HomeKit/characteristic-types) for a list of standard types. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)