The organism follows certain rhythms, like the day/night rhythm or also the summer/winter cycle, that proved to be vital in the course of the evolution. For example many people can imagine the influence of the moon on the organism since they can sleep only very badly or not at all on certain full moon days. These rhythms are called biorhythms. They are continuous, repeating cycles, causing physiological changes of the body. Whoever knows these rhythms should plan his life better and can shape more positively. The rhythms let themselves represent as sine curves and begin on the day of the birth. But on the basis of the continuous postponements of these sine curves against each other, all curves can be on the highest also as well as on the deepest point simultaneously. This online biorhythm calculator should help you to determine the 'bad' and also the 'good' days fast gratuitously online.