To check your own biorhythms enter your birthdate into the text box (using the same format shown - mm/dd/yyyy) and click 'Evaluate'.

Values range from -10 to +10. Values near or equal zero indicate criticalness. The sign after each value indicates either a rising (+) or falling (–) trend.

From the day we are born, we are governed by cycles. The 28-day cycle called the Emotional or sensitivity cycle governs one's temperament. The 33-day cycle, called the Intellectual cycle, influences our intellect or thinking capacity. The 23-day cycle called the Physical cycle governs the condition of one's body. Those who have investigated the theory seem to agree on the length of these cycles as 28, 33 and 23 days respectively.