The time it takes for weed (marijuana) to leave your system varies widely depending on factors such as frequency of use, body fat, metabolism, and the type of drug test used.

Detection Times by Test Type

• Urine tests: The most common testing method. Detection times range from about 3 days after a single use to over 30 days for chronic heavy users. Moderate users (around 4 times per week) may test positive for 5–7 days, while daily users might test positive for 10–15 days or longer. In extreme chronic cases, detection can last up to 70–90 days

• Blood tests: Detect THC for a much shorter period, typically 2–24 hours after use. In heavy chronic users, THC has been detected up to about 7 days after last use, but usually it is undetectable within 1–2 days

• Saliva tests: THC is detectable for about 24–72 hours after use. Saliva tests are often used for roadside testing and detect recent use rather than long-term presence

• Hair tests: Can detect cannabis use for up to 90 days. Hair testing tracks drug use over months, as cannabinoids are deposited in hair follicles via blood and sweat. However, hair tests are less reliable and can be affected by external contamination

Factors Affecting How Long Weed Stays in Your System

• Frequency and amount of use: More frequent and heavier use leads to longer detection times.
• Body fat percentage: THC metabolites are fat-soluble and stored in fat tissue, so higher body fat can prolong detection.
• Metabolism: Faster metabolism clears THC more quickly.
• Method of consumption: Edibles may take longer to clear than smoking.
• Genetics and overall health: Individual differences affect metabolism and excretion rates

Summary

• For occasional users, weed may be undetectable in urine after about 3 days.
• For regular or heavy users, detection in urine can last from 10 days up to 30 days or more.
• Blood and saliva tests detect more recent use within hours to a few days.
• Hair tests can detect use for up to 90 days.

Complete elimination of THC metabolites can take from a few days to over two months depending on these factors