Abstract: A firearm safety device includes one or more optical sensors fastenable to a trigger guard of a firearm and configured to detect a user's finger inside the trigger guard when the sensors are attached to the trigger guard and a detector to detect the position of the safety catch of the firearm. The device further includes an apparatus connected to the one or more optical sensors and the detector and activated when the sensors detect no finger inside the trigger guard and the detector detects the safety catch is off.