Biorhythm Calculator — Your Three Cycles

How to use

1. Enter your date of birth.
2. Pick the target date.
3. Read the three percentages and the chart.

About this tool

The biorhythm hypothesis says three cycles run from your birth: physical over 23 days, emotional over 28, intellectual over 33. Each is a plain sine wave, so the value on any date is exact arithmetic — days lived divided by the cycle length, times 2π. This tool plots all three as an SVG chart for the month around your target date and marks the critical days where a curve crosses zero, which is the part of the theory people actually use. The maths is verifiable; the interpretation is not established science. This tool applies traditional numerology and astrology rules exactly as those systems define them. Those systems are cultural traditions, not measured science, so treat the result as a prompt for reflection rather than a prediction.

FAQ

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