Biorhythm
The biorhythm theory models three cycles that begin at birth: a 23-day physical cycle, a 28-day emotional cycle and a 33-day intellectual cycle. Each rises and falls as a sine wave. Enter your birth date and any target date to see where each cycle sits and whether it's a high, low or 'critical' (zero-crossing) day.
It's a light, self-reflective tool — computed entirely in your browser.
Enter your details below to compute your result. Nothing is stored.
How to read your result
Positive percentages are the high (energised) half of a cycle; negative are the low (recharge) half.
'Critical' days are when a cycle crosses zero — traditionally seen as unstable for that area.
How it's calculated
For each cycle, value = sin(2π × days-since-birth ÷ period), shown as a percentage from −100% to +100%.
See this inside your full Kundali
This is one section of your birth chart. Generate the complete free Kundali — charts, dashas, doshas, panchang and more.
Frequently asked questions
What are the three biorhythm cycles?
Physical (23 days), emotional (28 days) and intellectual (33 days) — each modelled as a sine wave starting from your birth date.
What is a critical day?
A day when a cycle crosses the zero line between its high and low halves — considered the most changeable day for that cycle.
Is biorhythm scientific?
No — biorhythms are a popular self-reflection model, not a scientifically validated predictor. Use it for fun and reflection.