How To Test Testosterone Levels, Backed By Guidelines

To test testosterone levels accurately, get a morning blood draw between 8 and 10 AM, measure total testosterone on at least two separate days, and pair the numbers with a symptom review. Timing and repetition matter because testosterone swings through the day and from one draw to the next. An afternoon draw can give a misleading result, since levels are naturally lower later in the day. If you want to know how to test testosterone levels without redoing the whole thing later, the approach below reflects what major guidelines generally recommend, though the details can vary. You can start with an evaluation through Marek Health and a clinician-ordered panel.

Testosterone testing measures the hormone in your blood to check for deficiency. The standard first test is total testosterone, drawn in the early morning. A diagnosis of low testosterone generally rests on more than one low morning reading together with symptoms, not a number on its own, with the final assessment individualized by your provider (Mulhall et al., 2018). The result guides whether further hormone testing or a testosterone evaluation makes sense.

Why would you get a testosterone test?

Testing makes sense when you have symptoms that line up with low testosterone, not as a routine screen. The Endocrine Society advises against screening men who feel fine (Bhasin et al., 2018). Symptoms that warrant a look include low sex drive, erectile changes, fatigue, loss of muscle, more body fat, low mood, and trouble concentrating. These overlap with plenty of other conditions, which is why a lab number alone settles nothing.

Certain medical histories raise the odds enough that the AUA suggests measuring testosterone even without classic symptoms: unexplained anemia, bone density loss, type 2 diabetes, prior chemotherapy or testicular radiation, HIV, chronic opioid use, and pituitary problems (Mulhall et al., 2018). If any of those apply to you, a hormone panel is reasonable to discuss.

Worth saying plainly: testosterone tends to decline gradually with age in many men, though the rate varies and a modest age-related dip is not automatically a disease. Testosterone is not FDA-approved for low levels attributed to aging alone (FDA, 2025).

Which tests do you actually need?

A single testosterone number misses too much. Total testosterone is the screening test, but free testosterone, SHBG, and a few supporting markers explain why two men with the same total can feel completely different. SHBG (sex hormone-binding globulin) is the protein that binds most of your testosterone. When SHBG runs high or low, your total can look normal while the active fraction does not (Bhasin et al., 2018).

Here is a sensible panel and what each part does.

Total and free testosterone are not interchangeable. The AUA notes there's no clean conversion between them and no single free-testosterone threshold that defines deficiency (Mulhall et al., 2018). That's why a provider reads the panel together rather than reacting to one line.

When should you test? Timing is the part people get wrong

Test in the early morning, ideally 8 to 10 AM. Testosterone follows a daily rhythm that peaks in the morning and drops later, so the guideline protocol specifies early-morning draws (Mulhall et al., 2018). A level pulled at 4 PM can read meaningfully lower than the same man's 8 AM value, which is how mistimed tests produce false "low" results.

The morning rule holds across ages. The daily swing flattens somewhat in older men, but guidelines still call for morning draws so your two tests are measured the same way (Bhasin et al., 2018).

Do you need to fast?

Fasting isn't strictly required to measure testosterone, but it's worth doing if your panel includes glucose or a lipid check, which is common. Plan on 8 to 12 hours of fasting, water is fine, and hold coffee until after the draw. Food intake, particularly carbohydrate-heavy meals, may transiently lower levels in some people, so a fasted morning draw keeps things consistent.

How do you prepare for the test?

A few day-of and night-before habits keep your result from reflecting a bad night instead of your real baseline. None of this is fussy. It's about removing noise.

• Book the appointment for 8 to 10 AM and fast beforehand if glucose or lipids are included.

• Sleep normally the night before. Short or broken sleep may lower morning levels in some men.

• Skip hard training for 24 hours. A heavy session or long endurance effort can affect the reading for some people.

• Go easy on alcohol for a day or two beforehand.

• Write down every medication and supplement to review with your provider.

What lowers testosterone on test day?

Several everyday things temporarily suppress testosterone: poor sleep, acute illness or fever, recent intense exercise, and heavier drinking. Some medications matter more than lifestyle. Opioids, corticosteroids like prednisone, and certain other drugs can lower levels enough to change how a result reads (Bhasin et al., 2018). Tell your provider about opioid pain medication, steroids, past or current anabolic steroid use, over-the-counter testosterone products, clomiphene or hCG, and cannabis. Each one shifts interpretation.

Where can you get a testosterone test?

You have a few routes, and they differ mostly in how the result gets interpreted, not in the blood draw itself. A primary care visit can order the panel, though some default to total testosterone only, so ask for the fuller list. A telehealth provider that focuses on men's hormone health typically orders the right panel up front and reads it in context. Telehealth providers like Marek Health generally combine a licensed-clinician evaluation, lab work, and a review of results against your symptoms.

Direct-to-consumer lab orders let you check a level before seeing anyone, which some men prefer. The catch is interpretation. A number without a clinician reading it next to your history and a second confirmatory draw doesn't get you to a diagnosis.

At-home kits using finger-prick or saliva samples are the most convenient but are generally less reliable. Saliva testing may not reliably reflect blood levels. These can hint at a problem, but guidelines call for proper lab measurement, repeated, before any treatment decision (Bhasin et al., 2018). Treat an at-home result as a prompt to get tested correctly, not as an answer.

How do you read your results?

Lab reference ranges describe what's statistically typical for a population, not a personal target. One widely used standard comes from a study of healthy nonobese men aged 19 to 39, which set a harmonized range of 264 to 916 ng/dL for total testosterone (Travison et al., 2017). That range applies to that group; your lab's reported range may differ, and "normal for the population" is not the same as "normal for you with these symptoms."

For diagnosis, the AUA points to a clearer line. It describes a total testosterone consistently below 300 ng/dL, confirmed on two early-morning draws and paired with symptoms, as supporting a diagnosis of low testosterone (Mulhall et al., 2018). Note the word consistently. One reading under 300 doesn't settle it, and your provider weighs the full picture rather than a single cut-off.

A level near the bottom of the range alongside real symptoms is worth a proper evaluation. That's different from saying a specific number is a goal to hit. Treatment decisions rest on symptoms plus confirmed labs, which is why a clinician reviews your bloodwork rather than handing you a target.

How is low testosterone confirmed?

Confirmation takes more than one lab slip. Guidelines call for two separate morning measurements showing low total testosterone, symptoms that fit, and a check for other causes like thyroid disease, diabetes, or sleep apnea (Bhasin et al., 2018). Levels fluctuate enough that a single low draw can mislead, which is the whole reason for testing twice. When the cause needs sorting out, LH and FSH help point to whether the issue sits in the testes or the pituitary.

What testing looks like once you're on therapy

Testing doesn't stop once treatment starts. It changes purpose, from diagnosis to safety and dose-checking. The TRAVERSE trial, a large cardiovascular safety trial of testosterone therapy, studied men who already had cardiovascular disease or were at high risk. In that group, it found no increase in major adverse cardiac events versus placebo, while observing higher rates of certain events including atrial fibrillation and pulmonary embolism in the testosterone group (Lincoff et al., 2023). Whether testosterone therapy is appropriate depends on your individual risk profile and a discussion with your provider. On the strength of that trial, the FDA in February 2025 removed the older cardiovascular boxed warning and added a warning about increased blood pressure (FDA, 2025). Those findings are why monitored care tracks markers like hematocrit, blood pressure, estradiol, and PSA on a schedule rather than checking a level once and walking away. Your provider tailors the timing and any dose changes to your labs and goals, in discussion with you.

One practical point on injections: levels are usually measured at trough, just before the next dose, since that's your low point. Specific schedules and targets belong to your clinician, not a generic chart, and care is provided only after evaluation and where state law permits. If you're weighing whether to start, the getting-started path begins with testing and a clinical review, not a prescription.

Disclaimer: This blog post is intended for informational purposes only and should not be considered medical advice. Always consult a healthcare professional before making changes to your health routine.

FAQs

How do you test testosterone levels correctly? 

Get a blood test in the early morning, ideally between 8 and 10 AM, and measure total testosterone on at least two separate days before drawing any conclusion (Mulhall et al., 2018). Pair the numbers with a symptom review. Morning timing and a repeat draw are what separate an accurate result from a misleading one.

What is the normal range for a testosterone test? 

A study of healthy nonobese men aged 19 to 39 set a harmonized total testosterone range of 264 to 916 ng/dL (Travison et al., 2017). Your lab's reported range may differ. For diagnosis, the AUA uses a total testosterone consistently below 300 ng/dL, confirmed on two morning draws and paired with symptoms (Mulhall et al., 2018).

How many times do you need to test to confirm low testosterone? 

Twice. Guidelines call for two separate early-morning measurements showing low total testosterone, plus symptoms that fit and a check for other causes (Bhasin et al., 2018). Levels fluctuate from day to day, so one low reading isn't enough to confirm anything.

Does the time of day matter for a testosterone blood test? 

Yes, a great deal. Testosterone peaks in the morning and falls later in the day, so an afternoon draw can read falsely low. Both guideline protocols specify early-morning testing, and using the same timing for both draws keeps your results comparable (Mulhall et al., 2018).

Should you fast before a testosterone test? 

Fasting isn't strictly required for testosterone alone, but it helps if your panel includes glucose or lipids, which is common. Plan on 8 to 12 hours, drink water, and hold coffee until after the draw. A fasted morning draw also removes a food-related dip that can muddy the number.

Are at-home testosterone tests accurate enough for diagnosis? 

They're convenient but limited, and saliva-based kits may not reliably reflect blood levels. Guidelines call for proper laboratory measurement, repeated, before any treatment decision (Bhasin et al., 2018). An at-home result can flag a possible issue, but it shouldn't replace a confirmed morning lab draw.

What testing is needed after starting testosterone therapy? 

Monitoring shifts to safety. Providers track markers like hematocrit, blood pressure, estradiol, and PSA on a schedule, partly because the TRAVERSE trial, in men with high cardiovascular risk, recorded higher rates of certain events including atrial fibrillation and pulmonary embolism on testosterone, prompting the FDA's 2025 blood-pressure warning (Lincoff et al., 2023; FDA, 2025). Your clinician tailors the timing and any dose changes to your labs and goals.

References

• J Urol. 2018;200(2):423–432

• J Clin Endocrinol Metab. 2018;103(5):1715–1744

• J Clin Endocrinol Metab. 2017;102(4):1161–1173

• N Engl J Med. 2023;389(2):107–117

• FDA. Class-wide labeling changes for testosterone products. 2025