Testosterone tests are typically done by taking a blood sample and they will measure:, Total testosterone: This is the testosterone that’s both bound to proteins and also floating free., Free testosterone: This is the amount of testosterone that’s floating free and can be useful for ruling out some medical conditions., The gold standard for measuring testosterone levels is by mass spectrometry, where both the quality and quantity of molecules can be very accurately measured., Usually a doctor or healthcare professional will do the test in a lab, with results available in just a few days., For males under the age of 45 years, testosterone levels are often at their highest in the morning. For this reason, medical professionals will often advise to have you test first thing in the morning.