“I’m a 6’2” man and have 178 lbs. I have a drug test in 4 days, haven’t been smoking weed for a week. Will I pass a drug test? I have a regular cannabis smoking habit.”
The most common standard urine drug test can detect THC up to 90 days after inhalation/ingestion. Does that mean that everybody who has smoked a joint in the last 90 days will test THC positive? Of course not; it depends on how frequently you smoke, M/F and how much you weigh.
So if not 90 days, how long does weed stay in your body?
We looked into published scientific studies about how long does weed stay in your system. The goal of looking at more than 6000 gathered and tested urine samples was to answer how many days of marijuana abstinence is needed to pass a drug test for various subjects (male/female, underweight/overweight, one time users as well as chronic users).
The speed of weed elimination can be roughly estimated for every type of user:
- Male and female.
- One-time puffers all the way to heavy chronic marijuana users.
- Underweight people (skinny guys and girls with low body fat mass percentage) and overweight people (for example, an individual weighing 300 lbs passing a drug test is increasingly difficult).
In the end, you should know when will weed be cleansed out of your system if you’re a chronic user, a skinny woman, a fat man, somebody with over 200 pounds or a one-time user will less than 100 pounds. And everything in between, of course.
Calculator – How Many Days Does THC Stay In Your System
After helping out almost 200 people (in the comments), we have decided to put together a THC elimination calculator. You can input your sex, weight, height, metabolism and activity levels.
The calculator will give you a rough estimate of how long it will take for all the THC to be cleared out of your system for all times of users: light, moderate, frequent, heavy and chronic heavy.
You can use the calculator freely. Just keep in mind we are all unique and our system retains THC differently. These are only rough estimates.
If you estimate that you’ll fail a drug test, you should check out our article about Complete THC Detox to speed up the elimination of THC out of your body considerably.
Weed Elimination Times
Weed might be great for a number of reasons but THC elimination time is definitely not one of them.
Most of the other drugs (even hard drugs) leave our system in 1-3 days after ingestion. Unfortunately, marijuana can accumulate in your body and it takes significantly longer time to leave the system.
How long does weed stay in your system?
Simple short answer: 1 to 90 days.
Simple long(er) answer:
- One-time smokers: 2-7 days.
- “Weekend” smokers (1 joint/week): 5-10 days.
- Moderate smokers (3 joints/week): 10-17 days.
- Chronic smokers (7 joints/week): 17-30 days.
- Heavy chronic use (more than 10 joints/week): 30-48 days.
Scientific answer: It depends. Did you smoke just once or are you a chronic user? How tall are you and how much do you weigh? Male or female? What kind of a drug test are we talking about – urine test or hair test? What are your levels of physical activity and body fat mass?
We’ve prepared conglomerated lists of THC elimination times for men (tall, normal, short) and women (tall, normal, short).
For example, here is a list of estimated THC elimination times for an average high male (5’6” – 6’2”):
Average Height Male (5’6” – 6’2”)
|Average Male (5’6” – 6’2”)||150-200 lbs||200-250 lbs||250-300 lbs||300+ lbs||Recommended Detox:|
|1 joint once||2.9 days||3.5 days||4.2 days||5 days||Water|
|1 joint per week||5.7 days||6.5 days||7.3 days||8.2 days||Water + Physical Activity|
|3 joints per week||11.1 days||12.2 days||13.7 days||15.1 days||3-Day Toxin Rid|
|7 joints per week||18.6 days||21.1 days||24 days||26.9 days||5-Day Toxin Rid|
|10+ joints per week||33 days||35.1 days||38.6 days||41.6 days||10-Day Toxin Rid|
You can find 5 more THC elimination lists for down below.
- Tall male(above 6’2”)
- Short male (below 5’6”)
- Tall female (above 5’7”)
- Average height female (5’1” – 5’7”)
- Short female (below 5’1”)
Scientifically speaking there are a great number of factors that determine how long does it take for marijuana to leave our bodies.
For example, people with higher BMI (body mass index) test positive for THC days or even week longer than people with lower BMI.
To simplify it, we boiled down some research studies into simple enough figures for THC detection in urine. More than 90% of drug screening test urine for weed. If you’re faced with a lab test, you will almost certainly have to ‘pee in a cup’.
We do also assume you were smoking ‘some good sh*t’ (that translates into 3.55% THC cigarettes).
How Long Is Weed Present In Your Urine?
Most of the time when people talk about drug tests, they talk about the urine drug test.
Testing urine for marijuana (THC-COOH metabolite to be exact) is the standard procedure that employers use in order to determine if you’ve been using cannabis.
The length of time weed can be detected in urine is quite a disputed topic. We have two extreme anecdotal cases:
- “I’m get blazed all the time (loading some fat ones) and passed a lab test 3 days after my last joint with flying colors, bro.”
- “Went to Amsterdam, smoked a joint just to try it (that stuff was really good). A month later, I failed a drug test and was fired on the spot.”
Weed leaves your body in 3 days or in a month: which is it?
Sure, there are lots of this kind of anecdotal cases but nobody really likes to risk his or her job with something as serious as failing a drug test.
That’s why we used the result of a clinical study published in the renowned Journal Of Analytical Toxicology to base the calculation of how many days it takes for weed to leave your body.
The number of evaluated urine samples exceeded 6,000 individual samples.
The THC elimination times are categorized based on sex, height, weight and smoking habit.
That’s how everybody can find themselves in the tables below and get a good grip on how long does it take for weed to stay in their individual body.
After that, you can check out how to do a complete THC detox in order to cut the time it takes for THC to leave the body in half (or even more).
Tall Male (Above 6’2”)
With each of these cases, we segmented how long it takes for weed to leave your body by two factors:
- Cannabis smoking frequency.
Example: If you’re a tall male (above 6’2”) with a moderate smoking habit (3 joints a week) and weigh 198 pounds, the best estimate of how many days does weed stay in your system is 12.3 days.
Here is the estimation table of days after which weed is likely not detected in the urine of a tall man:
|Tall Male (Above 6’2”)||150-200 lbs||200-250 lbs||250-300 lbs||300+ lbs|
|1 joint once||2 days||2.6 days||3.3 days||4 days|
|1 joint per week||5 days||5.7 days||6.5 days||7.3 days|
|3 joints per week||10 days||11.2 days||12.5 days||13.9 days|
|7 joints per week||17 days||19.8 days||22.3 days||25.7 days|
|10+ joints per week||30 days||32.9 days||36 days||39.1 days|
Based on this data, we can answer the initial question. Here are the case data:
- Height: 6’2” (tall man)
- Weight: 178 pounds (fits into the 150-200 lbs segment)
- Days of abstinence: Haven’t smoked for a week and has an upcoming urine drug screening for marijuana in 4 days (11 days total).
- Smoking habit: Regular smoking habit should fit 3 joints/week category.
How long does it take for the weed to leave his body?
According to the rough estimates in the table, such an individual should pass a urine drug test in 10 days.
That’s how we can say with high probability that such an individual should pass a standard laboratory drug test for marijuana.
If, for example, he would hit the bong 7 times per week, the THC would sufficiently leave his body to pass a drug test in about 17 days. If this were the case, such an individual would most probably fail a urine drug test.
The following tables include calculated rough estimates of how long does THC stay in the body for other types of bodies:
Shorter Male (Below 5’6”)
|Shorter Male (Below 5’6”)||150-200 lbs||200-250 lbs||250-300 lbs||300+ lbs|
|1 joint once||3.8 days||4.5 days||5.2 days||6 days|
|1 joint per week||6.3 days||7.2 days||8.1 days||9 days|
|3 joints per week||12.2 days||13.4 days||14.8 days||16 days|
|7 joints per week||20.3 days||22.4 days||25.1 days||28 days|
|10+ joints per week||35.9 days||38.7 days||41.2 days||44 days|
Tall Female (Above 5’7”)
|Tall Female (Above 5'7'')||100-150 lbs||150-200 lbs||200-250 lbs||250+ lbs|
|1 joint once||3 days||3.6 days||4.2 days||5 days|
|1 joint per week||6 days||6.6 days||7.4 days||8.1 days|
|3 joints per week||11.5 days||12.5 days||13.6 days||14.7 days|
|7 joints per week||19.8 days||21.5 days||23.4 days||25.3 days|
|10+ joints per week||35 days||37.2 days||39.4 days||41.7 days|
Average Height Female (5’1” – 5’7”)
|Average Female (5'1'' - 5'7'')||100-150 lbs||150-200 lbs||200-250 lbs||250+ lbs|
|1 joint once||3.3 days||4 days||4.7 days||5.5 days|
|1 joint per week||6.5 days||7.2 days||7.9 days||8.6 days|
|3 joints per week||11.8 days||12.8 days||13.9 days||15 days|
|7 joints per week||21.2 days||22.7 days||24.3 days||26.4 days|
|10+ joints per week||37.1 days||39.2 days||41.4 days||43.6 days|
Shorter Female (Below 5’1”)
|Shorter Female (Below 5’1”)||100-150 lbs||150-200 lbs||200-250 lbs||250+ lbs|
|1 joint once||3.6 days||4.4 days||5.2 days||6.1 days|
|1 joint per week||7 days||7.8 days||8.4 days||9.2 days|
|3 joints per week||12.2 days||13.3 days||14.5 days||15.8 days|
|7 joints per week||22.6 days||23.9 days||25.2 days||27.6 days|
|10+ joints per week||39.2 days||41.3 days||43.5 days||45.7 days|
How To Calculate The Time It Takes For Weed To Leave The Body?
THC elimination times vary quite a lot between individuals.
Numerous studies were conducted producing non-coherent results. However, there is a silver lining connecting a majority of conducted studies of THC elimination speed.
Namely, certain ‘rules’ were observed:
- The heavier the smoking habit, the longer it takes for our system to eliminate THC.
- Higher BMI leads to longer elimination times. That’s why heavier people need longer time to detox.
- Higher body fat percentage leads to a prolonged time it takes for weed to leave the body. Because the total body fat percentage of women is significantly higher than in man, women need to detox longer.
One important factor is also the kind of urine THC tests that are being used. In the calculations above, it was presumed that the detection of THC in urine is being conducted with a standard drug screening test with a 20 ng/ml cut-off rate. Some laboratories might also be using an older lab screening test with 50 ng/ml cut-off rate.
When calculating the period after which THC is no longer detected in urine, the following factors were taken into the account:
- Smoking habit.
- BMI (as a conglomerate of height and weight).
Based on those and the available data from clinical studies the extrapolations (mostly linear) can be drafted.
Nonetheless, it is very important to understand that the THC elimination data in the tables are merely rough estimates and cannot 100% guarantee somebody with a certain body constitution, sex and smoking habit will pass or fail a drug test.
Share How Many Days It Took You To Detox From THC
If you have a personal experience and can shine a light at how long does it take for weed to leave the body, you can share it in the comments.
Example: “I passed a drug test despite being a heavy user (5’7”, male, 210 lbs). Did the whole abstinence thing and drank gallons of water for 15 days, passed with flying colors.”
Alternatively, if you have a question about your individual case, you can also place a comment that looks something like this:
“I have a drug test in 3 days, haven’t smoked for 5 days, will I pass? I’m 6’1” man, weigh 213 lbs and have been smoking 3 joints per week for ages.”
Some clinical studies and other sources:
(1) Goodwin RS, Darwin WD, Chiang CN, Shih M, Li SH, Huestis MA. Urinary elimination of 11-nor-9-carboxy-delta9-tetrahydrocannnabinol in cannabis users during continuously monitored abstinence. J Anal Toxicol. 2008;32(8):562-9.
(2) Huestis MA, Henningfield JE, Cone EJ. Blood cannabinoids. I. Absorption of THC and formation of 11-OH-THC and THCCOOH during and after smoking marijuana. J Anal Toxicol. 1992;16:276–82.
(3) Reiter A, Hake J, Meissner C, Rohwer J, Friedrich HJ, Oehmichen M. Time of drug elimination in chronic drug abusers. Case study of 52 patients in a “low-step” detoxification ward. Forensic SciInt. 2001;119:248–253.
(4) Sharma P, Murthy P, Bharath MM. Chemistry, metabolism, and toxicology of cannabis: clinical implications. Iran J Psychiatry. 2012;7(4):149-56.