Astrology & Numerology
Biorhythm calculator
Physical, emotional and intellectual cycles on a given date.
- Instant
- Free
- Private (processed locally)
- No sign-up
Calculate your biorhythm
Enter your birth date and a target date: the tool gives the three cycles, from −100% (low) to +100% (high).
The three cycles
- Physical: 23 days
- Emotional: 28 days
- Intellectual: 33 days
- value = sin(2π × days ÷ period)
For fun, no scientific validity. 100% local calculation.
Frequently asked questions
How does biorhythm work?
Each cycle is a sine wave from birth: value = sin(2π × days / period), from −100% (low) to +100% (high).
What are the periods?
Physical 23 days, emotional 28 days, intellectual 33 days.
What does 0% mean?
A “critical” day where the cycle crosses zero: the theory links it to instability.
Is it scientific?
No, biorhythm is entertainment with no proven scientific validity.