There are hundreds of different cannabinoids but most drug tests detect THC, which is the active ingredient in marijuana. Various factors will influence the length of time that cannabinoids like THC stay in your system, such as your frequency of use, body mass, gender, metabolism, and hydration.
Below are approximate drug test detection times for marijuana:
Blood: A few hours
Saliva: A few hours
Urine: Up to 13 days for one-time use, up to 45 days for regular use, and up to 90 days for heavy use
Hair: Up to 90 days