Biorhythm Calculator
Explore your physical, emotional, and intellectual cycles based on your birth date.
Your body is energized — great day for exercise, sports, and physical work.
You may feel withdrawn or sensitive — be gentle with yourself.
Mental fatigue is possible — avoid high-stakes decisions if you can.
30-Day Cycle Chart
PhysicalEmotionalIntellectualUpcoming Notable Days (Next 10 Days)
Understanding the Cycles
About Biorhythm Calculator
Biorhythm theory, popularized in the 1970s, proposes that our bodies follow three innate sinusoidal cycles starting from the moment of birth: a 23-day physical cycle, a 28-day emotional cycle, and a 33-day intellectual cycle. The formula is simply sin(2π × daysLived / period) × 100.
Critical days — when a cycle crosses zero — are considered transition points where that dimension of your wellbeing is unstable. Peak days (value above +90) represent your highest potential in that cycle, while low days (below −90) suggest a period of recovery.
All calculations run entirely in your browser. No data is sent to any server, and the tool works offline once loaded.