About

My name is Tomasz Fiedoruk and I am the author of this website, the app and the study. I first came across biorhythms over 30 years ago. I think I know every biorhythm site and app out there — and to this day I haven't found the perfect one. So I decided to build it myself. But that's not all: on a solid scientific basis, I want to run an anonymous study that will confirm or disprove the effectiveness of this method once and for all. Each of you can take part anonymously — thank you in advance, in the name of science! :)

aimy.bio is a free, fully private biorhythm app based on the method of Dr. Jerzy Sikora. It was built as a tribute to his work in this unusual field.

Dr. Jerzy Sikora's method

Unlike the popular sine-wave model, Dr. Jerzy Sikora's method describes biorhythms as discrete phases with four states: high (+), low (−), critical day (X) and zero day (0). Each of the three cycles — physical (23 days), emotional (28 days) and intellectual (33 days) — has its own precise phase layout, with the emotional cycle notably having two critical days.

The method also applies a birth-time correction (different for those born in the morning vs the afternoon) — a detail omitted by simplified calculators yet essential for consistency with the source materials.

How it differs from the sine wave

Most calculators draw a smooth sine wave and read percentages off it. In Sikora's method the meaning lies in specific days — above all the critical day (X) and the zero day (0) — not in the shape of the curve. In this app the sine wave is used for visualisation only; the phase symbols tell you what a given day actually is.

History and validation

The app's calculations were reconstructed and validated against Dr. Sikora's 1983 book Biodiagram prawdę Ci powie. The engine is guarded by a set of golden vectors (shared between the web and mobile versions) so it stays faithful to the original through every update. The method and a verified reference engine are open source — an inspectable, lasting tribute; see the reference implementation on GitHub.

The first online version appeared in 2025. This edition is a full reconstruction of the method, running entirely in your browser — no accounts, and no server computing anything on your behalf.

What it is — and isn't

The app is free, with no accounts, ads or paywalls. We treat biorhythms reflectively — this is a wellness tool, not medical advice or a predictive instrument.

More about me →

This site stands as a tribute to the work of Dr. Jerzy Sikora.