Active RFID is a technology based on data transmission by radiofrequency signals

Unlike passive RFID tags, active RFID tags have their own internal power source which is used to power any Integrated Circuits that generate the outgoing signal. Active tags are typically much more reliable (e.g. fewer errors) than passive tags due to the ability for active tags to conduct a "session" with a reader. Active tags, due to their onboard power supply, also transmit at higher power levels than passive tags, allowing them to be more effective in "RF challenged" environments like water (including humans/cattle, which are mostly water), metal (shipping containers, vehicles), or at longer distances. Many active tags have practical ranges of hundreds of meters, and a battery life of up to 10 years.

Some active RFID tags include sensors such as temperature logging which have been used in concrete maturity monitoring or to monitor the temperature of perishable goods. Other sensors that have been married with active RFID include humidity, shock/vibration, light, radiation, temperature, and atmospherics like ethylene.

Active tags typically have much longer range (approximately 100 m/300 feet) and larger memories than passive tags, as well as the ability to store additional information sent by the transceiver.