Three lives, three rhythms.
A biorhythm is a simple idea: from the day you were born, three cycles repeat like slow waves — one for your body, one for your feelings, one for your mind. Where each wave sits today is said to color the day. Pick a person to see their waves up close — or add any birth date of your own below.
Check another birth date
Tap the date field to open the calendar picker, choose a birth date, and that person's waves appear alongside the others. Pin an added date from its tab and it stays on the board for your next visit, just like the three above; unpinned dates last for this visit only.
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The shaded center line is the day in focus. Dots on the zero line mark critical days — the moment a wave crosses from high to low or back, traditionally read as an unsteady, take-it-easy day for that cycle.
The day at a glance
Coming up
Everyone today
How in sync are they?
Compatibility compares where each pair's waves sit today. Near 100% means the two people's cycles rise and fall together; near 0% means they're at opposite points.
The three cycles, in plain words
Physical — 23 days
Your body's wave: strength, stamina, coordination, and how fast you bounce back. High days suit hard effort and sport; low days are for rest and repair. It completes a full up-and-down round every 23 days.
Emotional — 28 days
Your feelings' wave: mood, patience, sensitivity, and creative spark. High days feel warm and intuitive; low days can feel flat or touchy. It runs on a 28-day round — roughly the length of a moon cycle.
Intellectual — 33 days
Your mind's wave: focus, memory, logic, and how easily new ideas click. High days suit study, planning, and hard problems; low days favor routine work over big decisions. One full round takes 33 days.
How to read the numbers: each cycle is shown from −100% (bottom of the wave) to +100% (the very top). A "critical day" is when a wave crosses zero — tradition treats those as wobbly days for that one part of life, worth a little extra care. Biorhythms are a century-old folk model, not medical science — enjoy them as a lens for reflection, not as advice.