Questions?

Supported browsers

Firefox, Google Chrome, (Safari: only Mac)
Android*, iOS*

Save birthdays

Names and birthdays can be saved as presets. The data is stored on your device. Note: The data can not be stored or read in private mode.

Other languages

Translate the site in your language (beta-version):
click here:

* Full view smartphones/tablets

Click on on the mainscreen below for full view. If distorted, turn tablet or smartphone briefly to 90 degrees and back again.

Old Java-Version

The old Java-applet of the biorhythm-application runs only on old systems as Microsoft XP or Mac 10.6.8 -> click here

How to calculate biorhythms?

At the birth-date, the sinus-curves start to swing at the zero-point (going upwards). The periodtime for the
- Physical curve is: 23 days
- Emotional curve is: 28 days
- Intellectual curve is: 33 days

Formulas for the 3 curves:
state (age in days) = 100% * sin ( 2*PI *(age / 23))
state (age in days) = 100% * sin ( 2*PI *(age / 28))
state (age in days) = 100% * sin ( 2*PI *(age / 33))
(2*PI = 360 degrees)

Example: Physical curve for somebody, who is 10'000 days old today:
state (10'000) = 100 * sin ( 360 *(10'000 / 23)) = - 98%

When calculating the «age in days» the leap days of course have to be regarded.

Will biorhythms repeat during life?

The curves will have the same state like birth exactly 23*28*33 = 21252 days after birth again.
This will be at the age of 58 years, 2 months and about 7 days (depending on the position of the leap years and length of the month).

Do animals have biorhythms?

The theory of biorhythms with its specific duration of the cycle periods was detected by a professor, when he inquired the state of condition of his students over a year. So he found a coherence between the condition (of humans) and the specific time-periods. Animals do have biorhythms probably too, but it has to be inquired whether they are similar or different (even for different species). I have never heard about such inquiries.

Tell friends about this site

Send your friends an automaticly generated email -> click
or join the biorhythms-discussion-group

Luck Cycles

Sometimes I am asked, if there are any «luck cycles». I have never heard about such cycles with regular periods . I can mention the story of Fortuna, the goddess of luck in Roman mythology.  Fortuna was associated only with good fortune in early Roman religion.  However, after she became identified with Tyche, the Greek goddess of chance, she was also considered a bearer of bad luck.  Fortuna often is shown with a wheel that she turned to bring success or failure.  She also appears with a rudder, symbolizing her power to steer people's lives.  The word fortune comes from her name.