Biorhythm Calculator
Calculate your physical, emotional, and intellectual biorhythm cycles based on your birth date.
See your peak and low days.
Your Biorhythm
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Biorhythm theory proposes that three biological cycles begin at birth and oscillate in regular sine wave patterns throughout your life.
The three cycles:
- Physical (23 days): Strength, coordination, stamina
- Emotional (28 days): Mood, creativity, sensitivity
- Intellectual (33 days): Thinking, memory, analytical ability
The formula for each cycle:
Value = sin(2π × days_alive / cycle_length) × 100%
Interpreting the values:
- +100%: Peak — highest performance for that cycle
- 0%: Critical day — transitional, be cautious
- −100%: Low point — conserve energy
Critical days (when a cycle crosses zero) are said to be days of instability. When multiple cycles cross zero on the same day, extra caution is advised.
Note: Biorhythms are not scientifically validated. They are a popular curiosity and self-reflection tool.