what blood type is universal donor

The universal blood donor type is blood type O negative (O-). This blood type can be given safely to people of any other blood type because it lacks A, B, and Rh antigens that could trigger an immune response in recipients. O negative blood is especially used in emergencies when the recipient's blood type is unknown, making it the most critical and in-demand blood type for transfusions. In contrast, for plasma donations, the universal plasma donor is blood type AB, and for universal recipients, the blood type AB positive (AB+) can safely receive blood from any type. Thus, O negative is the universal donor blood type for red blood cells and whole blood transfusions.