How long does weed stay in your system?
Rough detection windows for urine, blood, saliva, and hair tests, what actually gets detected, and the factors that stretch or shrink the timeline.
Updated July 7, 2026 5 min read
Drug tests don't look for the cannabis "high." They look for THC metabolites, mainly THC-COOH, which your body stores in fat and releases slowly. That storage is why cannabis is detectable long after its effects are gone, and why the honest answer to "how long" is: it depends.
Typical detection windows
Urine tests, the most common kind, generally detect occasional use for about 3 days, regular use for 5-7 days, daily use for 10-15 days, and heavy long-term use for 30 days or more. Saliva tests usually reach back 24-72 hours, blood tests a few hours to a couple of days, and hair tests up to 90 days.
What moves the numbers
Frequency matters more than anything: metabolites accumulate with daily use, so a one-time smoker and a daily consumer are on completely different clocks. Body fat, metabolism, potency, and dose all play a role too. Edibles and smoking end up in the same place for testing purposes: the metabolites are the same.
Can you speed it up?
Mostly no. Detox drinks, saunas, and crash exercise routines are not reliably supported by evidence. Time is the only dependable factor. Hydration and exercise support your normal metabolism, but nothing credibly converts a 30-day window into a 3-day one.
Frequently asked questions
How long is weed detectable in urine?
Roughly 3 days after one-time use, 5-7 days for regular use, and 30+ days for heavy daily use. Individual results vary with body composition and metabolism.
Do edibles stay in your system longer than smoking?
Tests detect the same THC metabolites either way. Detection windows are driven by how much and how often you consume, not by the format.