A cortisol urine test is also known as urinary free cortisol test or UFC test. This test measures the amount of cortisol in your urine for 24 hours. Cortisol is a hormone produced by adrenal glands that are located on top of kidneys. The glands release this hormone in form of a reaction given by the body for physical and emotional stress. Cortisol levels rise 9•and fall naturally throughout the day. Usually the level of the hormone is highest during morning and lowest during midnight. This might vary from person to person. Cortisol urine test is performed to determine the reason of abnormal cortisol levels.