Biorhythm changelog

Every change to the Biorhythm calculator, newest first.

Current version: [2.0] — 2026-10-11

[2.0] — 2026-10-11 - Rebuilt, for the whole family

Several people on one device (you, your wife, the kids): their names sit along the top, one tap to switch, ＋ to add, ✎ to edit.
Your own links: a link for each person, and Link with everyone that puts the whole list on another device. Email it to myself keeps it as a backup if the browser's data is ever cleared.
The Today card shows whose numbers they are: "Joe, born Apr 17, 1982 · age 44".
Today's three cycles in plain words, with rising and falling arrows.
A tappable 30-day chart; step by day or week, or pick any date.
Best days and critical days for the next 30 days. Critical days show which way the cycle turns: green ↑ turning up into a high stretch, red ↓ turning down into a low one.
Compare any two people, or anyone by birth date.
Extra cycles: intuitive, aesthetic and spiritual.
What the research says: the history of biorhythms, the exact formula used, and what 134 studies found, with sources.
💾 Back up your list shortcut that jumps straight to Email it to myself.
Install it like an app, with its own icon (Chrome: Install app; iPhone: Share, Add to Home Screen). Works with no signal once opened.
Dark by default, with Light and Auto.

Runs entirely in your browser: names and birth dates never go to the server (the old version sent the date in the address). Old links still open the right day.
Laid out for phones (and still roomy on computers): once someone is saved, the setup folds to one row of name buttons, so the cycles and chart fit on one screen.

Biorhythm calculator: enter a birth date, see a 30-day chart of the physical, emotional and intellectual cycles, step 30 days at a time.