Every PED, including SARMs and other research chemicals (RCs), has its own unique properties in terms of metabolization and clearance from your system.
Different SARMs and RCs will stay in your system for different periods of time, leaving metabolites in your urine, blood, and hair. The principle by which you get caught using them is the same as with any other performance-enhancing drug. Doping tests scan for the presence of these metabolites in your urine or blood.
Most SARMs are proven to be detectable from 9 to 21 days after a single dose administration. This varies from SARM to SARM. Some SARMs have little research behind them, so the detectability time for them is still unknown.
Here’s how long each SARM is detectable by drug tests screening for metabolites in urine and blood:
How Long Do SARMs Stay Detectable
These below-listed detection times are based on the latest doping control research by organizations such as the Institute for Doping in Moscow. They tested urine samples following the days and weeks from subjects who were given a single dose administration of a SARM or performance-enhancing research chemical.
All of the research papers referenced throughout this article are linked at the very bottom under the “References” tab.
Ostarine - MK2866
Ostarine is detectable in urine for approximately 2 weeks after a single dose administration. 
Ostarine was tested in a controlled single-dose administration study of 30mg in different volunteers. Urine was collected for the following 3 weeks. Ostarine metabolites were detectable in urine for ~ 2 weeks after the 30mg administration across all of the volunteers.
Andarine - S4
Andarine is detectable in urine for approximately 2 weeks after a single dose administration. 
Just like Ostarine, Andarine was tested in a controlled single-dose administration study where different volunteers were given 60mg. Urine was then collected for the following 3 weeks. Andarine metabolites were detectable in urine for ~ 2 weeks after the 60mg administration across all of the volunteers.
Ligandrol - LGD 4033
LGD 4033 is detectable in urine for up to 20.5 days. 
Multiple elimination studies have been done testing for metabolites after giving volunteers micro, and normal doses of LGD 4033. It was shown to be detectable as early as 11 days after a tiny dose of 50 µg. The maximum detection time for Ligandrol was shown to be 20.5 days in which 11 metabolites were detected.
Testolone - RAD 140
RAD 140 is detectable in urine for up to 8 days in urine. 
RAD 140 was tested in a controlled single-dose administration study where volunteers were given 10 mg. RAD 140 was shown to be detectable in urine for at least 8 days after the administration.
YK11 is detectable in urine for up to 48 hours after administration. 
The detectability period of S23 is unknown as it has not been thoroughly researched for doping control.
The detectability period of LGD 3303 is unknown as it has not been thoroughly researched for doping control.
The detectability period of ACP 105 is unknown as there is no human data at the time of writing.
But, there is one study that examined its detection in racehorses.
According to a study on the detection of ACP-105 and its metabolites in racehorses after oral administration, it was found that a total of 19 metabolites were detected in ACP-105 drug-administered equine urine samples. The study results suggest that ACP-105 and its metabolites were detectable in urine for up to 72 hours. 
This makes sense as ACP-105 is reported to have a very short half-life.
Ibutamoren - MK677
MK-677 is detectable in urine for 2 weeks. 
MK-677’s detectability was tested in a single-dose administration study where volunteers were given 10 mg. Then urine was collected in the following weeks. MK-677 metabolites were detected up to the 12th day following the single-dose administration.
Cardarine is detectable in urine for up to 40 days. 
Will SARMs Fail a Drug Test
None of the SARMs will cause you to fail standard drug tests. You will only be caught if you are tested for doping agents by a sports organization that has explicitly banned SARMs and/or follows WADA’s anti-doping policies.
SARMs will not show up on military, work, police, or firefighter drug tests.
But, if you somehow end up getting fake or tainted products that contain traces of anabolic steroids, you might fail a drug test for something you didn’t know you were taking.
If you’re expecting a drug test that explicitly bans SARMs, be prepared to stop taking your SARM for at least double its current known metabolite detectability status (just to be safe).
Most of the studies quoted in this article are not large-scale studies that include tens or hundreds of participants, nor did they test for metabolites after long-period SARM use. So it would be fair to assume that the longer you use a SARM the longer it would take for the metabolites to clear from your body.
Things like weight, height, activity level and hormone panel come into play as well. And the truth is, that it’s incredibly unpredictable.
Be very cautious, and critical. Good luck.