How Accurate are Marijuana Home Drug Tests?

Beginner Grow Guide is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to If you click on a link on this site that takes you to Amazon, I will earn a small commission and help keep the lights on at no extra cost to you 🙂

Although many businesses are struggling to find good workers, they’re still adhering to strict guidelines when it comes to drug testing. In fact, drug testing is a standard procedure with a lot of companies nationwide.

In addition, most employers have mandatory marijuana testing for new employees. In the same way, some businesses have random marijuana testing to minimize

Why are Companies Testing – Marijuana is Legal?

Yes, marijuana is legal in some states, but not all states. However, it is considered a Schedule 1 drug that is actually illegal under federal law.

In result, many companies have decided that it’s best to keep their employees safe by supporting a drug-free work environment. Not only are employers responsible for an employee’s well-being on the job but screening applicants before they are hired will eliminate any risk associated with a potentially inapt candidate.

In addition, businesses can prevent legal liability when they drug-test their employees.

Close-up detail of Cannabis, trichomes and leaves on late flower

Despite the fact that many Americans can legally access cannabis, pre-employment drug testing is still mandatory with various businesses. Additionally, some states require that you take a drug test before you can receive unemployment benefits or state assistance like food stamps.

On the other hand, you can do a drug test at home before you take the official test for employment or other reasons. In fact, home drug tests are easily found in numerous places such as drug stores or online.

Home drug tests are also inexpensive and easy to use.

What Exactly is a Home Drug Test?

A home drug test is a substance test that you can do at home. The test can tell you what substances are in the body.

In fact, a home drug test can identify almost any substance, depending on the type of test that you buy. Generally, drug tests are labeled as panels.

The panels are in reference to the type of drugs that are tested and identified.

  • 5 panel – tests and identifies marijuana, opiates, cocaine, amphetamines, and PCP
  • 6 panel – tests and identifies all substances in 5 panel plus benzodiazepines, such as Valium
  • 8 panel – tests and detects the presence of marijuana, opiates, cocaine, amphetamines, PCP, barbiturates, methamphetamine, and benzodiazepines
  • 10 panel – tests and identifies marijuana, opiates, cocaine, amphetamines, PCP, barbiturates, methadone, benzodiazepines, Quaaludes, and propoxyphene
  • 12 panel – an extensive test that detects marijuana, opiates, cocaine, amphetamines, PCP, barbiturates, methadone, benzodiazepines, Quaaludes, propoxyphene, Percocet/ oxycodone, and ecstasy/MDMA
  • 15 panel – tests and detects all of 12 panel plus tramadol, methaqualone and meperidine. As well, alcohol can sometimes be included in the 15 panel testing. However, because a urine test can have a false positive, the tester uses a breathalyzer.

Is a Home Drug Test Very Accurate?

Basically, there are two types of home drug tests, oral or saliva fluid tests and urine tests. Oral and saliva fluid tests are the least common and accurate.

This is because they have a short window of detection. In other words, the amount of time that has lapsed if a drug was taken is very minimal.

A urine test is the most accurate and common. They have a much longer window span than oral or saliva fluid tests and are also cost effective.

Cannabis or marijuana urine test

A blood test can actually measure the amount of drugs in the system. As well, it can detect impairment.

These tests are one of the most difficult to pass if you are a heavy cannabis user or if you have used cannabis for an extended amount of time. Hair tests have the longest window span and can detect the history of drug use in the body.

For instance, if marijuana was used for a certain amount of time, refrained from, then resumed, a hair test will confirm that. However, the results are sometimes inaccurate due to dust and pollen contaminants.

For the most part, home drug testing is pretty accurate. In fact, many tests claim 99% accuracy.

Top view of container with sample and doping drugs test lettering on blue

However, it does depend on the test. Generally, the more substances that are tested such a 15 panel, the better and more accurate the results.

Keep in mind that home tests can be rather sensitive. If the results are positive, then a lab test will definitely be positive. On the other hand, it is easy to get the wrong results with a home test.

This is because outside factors can alter the accuracy.

  • Is the sample contaminant free?
  • Not testing within the window of detection
  • Current prescription medications the user is taking
  • Is the urine the appropriate temperature, between96-99°F (35-37°C)?

In addition, the test can show a negative if it has exceeded its expiration date. As well, the test chemicals may not be working correctly.

Relying on a home drug test is probably not the best idea, especially if the upcoming lab test has any consequences. Nonetheless, it does not hurt to get a few home drug tests so that you have an idea whether or not you will pass the forthcoming lab test.

What if You Tested Positive on Your Home Drug Test

If you do a home drug test and test positive, you can always get additional analysis done. Keep in mind that home drug tests only disclose what is in your system.

Unfortunately, a home drug test does not tell you how much of the substance is in your body.

This information is vital. Passing the drug screening will highly depend on detectable levels of abstinence of a particular drug.

Drug test blank form

For instance, the cut-off for THC is 50ng/ml. In addition, if you tested positive and you have a lab test soon, there are certain things you can do to increase your chances of passing a urine test.

These tips are very helpful, especially if you need cannabis for medicinal reasons resulting in heavier use.

  • Try a home detox product
  • Postpone the test if absolutely necessary
  • Try and reduce body fat by lowering you calorie intake
  • Samples should be taken from mid-stream, not at the end or beginning
  • Stop using the substance as soon as you know about a mandatory lab test
  • Never provide the first pee of the day as a sample. Your first pee is more concentrated
  • Drink plenty of water to flush the system, but not so much as to water down your urine sample
  • Partake in regular exercise then stop 24 hours prior to the test. This releases THC metabolites from fat cells

Pros & Cons of Home Drug Testing

Whether you are a heavy cannabis user or use marijuana for medicinal purposes, lab drug testing can be pretty stressful. One of the best ways to reduce the anxiety is to do home drug test to see where you stand.

However, there are both pros and cons to home drug testing


  • Quicker results
  • Home tests are anonymous
  • You will know what to expect from the lab test


  • Easy to cheat on results
  • Does not show what caused you to fail the test.
  • It does not offer detailed results. For example, results are “pass” or “fail.”


A home drug test is fairly accurate. That is, if the test is done properly. To avoid false positive or negative, make sure that you perform the test correctly and use a quality test that offers accurate results.

If you decide to do a home drug test, make sure to follow the instructions precisely. In fact, it is highly recommended that you know how to do the drug test prior to taking it.

3D rendering of anti doping blood test tubes

In addition, pay attention to the window of detection and accuracy for the substance you are testing for. Likewise, give a clean sample by avoiding contaminants like dust.

A home drug test can be a very useful tool. However, the best and only way to be 100% sure that you’ll pass an upcoming lab test, it complete abstinence.

In addition, short or long term abstinence will greatly protect your means of support and livelihood.