The long view of three cycles

Life-Cycle Milestone Chart

Mark birthdays, paired crossings and the rare occasions when all three classic biorhythm cycles meet or fully reset.

Ages 80–90Return to my current decade
19 Oct 2076 to 19 Oct 2086

Your cycle crossings

42markers in this window
Biorhythm milestones between ages 80 and 90Six tracks mark birthdays, paired zero crossings, triple crossings and complete resets. Birthdays Physical + emotional Physical + intellectual Emotional + intellectual All three at zero Complete reset age 80age 81age 82age 83age 84age 85age 86age 87age 88age 89age 90 19 Oct 2076 12:00 — 80th birthday. A personal anniversary marker. 21 Oct 2076 00:00 — Physical + intellectual. Both cycles cross zero together. 9 Jan 2077 12:00 — Physical + emotional. Both cycles cross zero together. 2 Oct 2077 12:00 — Emotional + intellectual. Both cycles cross zero together. 19 Oct 2077 12:00 — 81st birthday. A personal anniversary marker. 4 Nov 2077 12:00 — Physical + intellectual. Both cycles cross zero together. 27 Nov 2077 12:00 — Physical + emotional. Both cycles cross zero together. 15 Oct 2078 12:00 — Physical + emotional. Both cycles cross zero together. 19 Oct 2078 12:00 — 82nd birthday. A personal anniversary marker. 19 Nov 2078 00:00 — Physical + intellectual. Both cycles cross zero together. 7 Jan 2079 12:00 — Emotional + intellectual. Both cycles cross zero together. 2 Sep 2079 12:00 — Physical + emotional. Both cycles cross zero together. 19 Oct 2079 12:00 — 83rd birthday. A personal anniversary marker. 3 Dec 2079 12:00 — Physical + intellectual. Both cycles cross zero together. 13 Apr 2080 12:00 — Emotional + intellectual. Both cycles cross zero together. 20 Jul 2080 12:00 — Physical + emotional. Both cycles cross zero together. 19 Oct 2080 12:00 — 84th birthday. A personal anniversary marker. 17 Dec 2080 00:00 — Physical + intellectual. Both cycles cross zero together. 7 Jun 2081 12:00 — Physical + emotional. Both cycles cross zero together. 19 Jul 2081 12:00 — Emotional + intellectual. Both cycles cross zero together. 19 Oct 2081 12:00 — 85th birthday. A personal anniversary marker. 31 Dec 2081 12:00 — Physical + intellectual. Both cycles cross zero together. 25 Apr 2082 12:00 — Physical + emotional. Both cycles cross zero together. 19 Oct 2082 12:00 — 86th birthday. A personal anniversary marker. 24 Oct 2082 12:00 — Emotional + intellectual. Both cycles cross zero together. 15 Jan 2083 00:00 — Physical + intellectual. Both cycles cross zero together. 13 Mar 2083 12:00 — Physical + emotional. Both cycles cross zero together. 19 Oct 2083 12:00 — 87th birthday. A personal anniversary marker. 29 Jan 2084 12:00 — Physical + emotional. Both cycles cross zero together. 29 Jan 2084 12:00 — Physical + intellectual. Both cycles cross zero together. 29 Jan 2084 12:00 — Emotional + intellectual. Both cycles cross zero together. 29 Jan 2084 12:00 — Three-cycle zero crossing. Physical, emotional and intellectual cycles meet at zero. 19 Oct 2084 12:00 — 88th birthday. A personal anniversary marker. 16 Dec 2084 12:00 — Physical + emotional. Both cycles cross zero together. 12 Feb 2085 00:00 — Physical + intellectual. Both cycles cross zero together. 5 May 2085 12:00 — Emotional + intellectual. Both cycles cross zero together. 19 Oct 2085 12:00 — 89th birthday. A personal anniversary marker. 3 Nov 2085 12:00 — Physical + emotional. Both cycles cross zero together. 26 Feb 2086 12:00 — Physical + intellectual. Both cycles cross zero together. 10 Aug 2086 12:00 — Emotional + intellectual. Both cycles cross zero together. 21 Sep 2086 12:00 — Physical + emotional. Both cycles cross zero together. 19 Oct 2086 12:00 — 90th birthday. A personal anniversary marker.
BirthdayTwo cyclesAll three at zeroComplete reset
Physical + intellectual21 Oct 2076age 80.0 · Both cycles cross zero together.
Physical + emotional9 Jan 2077age 80.2 · Both cycles cross zero together.
Emotional + intellectual2 Oct 2077age 81.0 · Both cycles cross zero together.
Physical + intellectual4 Nov 2077age 81.0 · Both cycles cross zero together.
Rare whole-life markers

When all three classic cycles meet

Triple crossingAge 29.1

All three classic cycles meet at zero.

Triple crossingAge 58.2

All three classic cycles meet at zero.

Complete resetAge 58.2

All three cycles restart in their original direction.

Triple crossingAge 87.3

All three classic cycles meet at zero.

Crossing versus reset

Zero is a meeting point, not always a restart

Every classic cycle crosses zero twice per cycle: once while rising and once while falling. Two cycles can therefore share a zero crossing without restarting in the same direction.

A three-cycle zero crossing repeats after 10,626 days (about 29.1 years). A complete reset, with all three returning to zero in their original upward direction, repeats after 21,252 days (about 58.2 years).

Difference between a zero crossing and a full resetThree sine waves cross the centre line together, while arrows show that direction determines whether the moment is a full reset.shared zero crossingdirection decides reset
What the mathematics says

Why these dates repeat

Physical + emotional

Their zero crossings coincide every 322 days.

Physical + intellectual

Their zero crossings coincide every 379.5 days.

Emotional + intellectual

Their zero crossings coincide every 462 days.

These are mathematical coincidences within classic biorhythm theory, which is not scientifically established. The chart is for reflection and entertainment, not prediction.

Continue exploring

Move between a single day, a month, a whole year or the longer story of your cycles.

Daily view Biorhythm Calculator Zoom into the physical, emotional and intellectual curves around a chosen day. Month view Personal Calendar Follow the three classic cycles through a focused month-by-month calendar. Two people Compatibility Chart Place two personal patterns together and explore where their rhythms align. Seven rhythms Extended Chart Add intuition, creativity, awareness and spiritual cycles to the classic three.