♃ Free Jupiter Return Calculator: Every Pass, Not Just One Date

Umbriel's free Jupiter return calculator finds the exact dates Jupiter comes back to its birth degree, roughly every twelve years.

A Jupiter return is Jupiter arriving back at the degree it occupied when you were born. Jupiter takes just under twelve years to circle the zodiac, so the returns land near ages 12, 24, 36, 48, 60, 72 and 84: the ages a great deal of folk wisdom about twelve-year chapters is built on. It is traditionally read as an opening: a new cycle of growth in whatever part of the chart Jupiter occupies.

The detail most calculators drop is that it is usually not one date. Jupiter retrogrades for about four months of every year, so it very often crosses its natal degree, backs over it, and crosses again: three exact passes spread across half a year or more. Quoting only the first means quoting a third of the answer, and anyone planning around a single date is planning around the wrong shape of event.

Umbriel lists every pass and says which one the return is dated from. It also flags a clipped result rather than presenting it as a whole one: the number of passes is always odd, so an even count means the search window cut a pass off, and a tidy incomplete answer is worse than a visibly incomplete one.

This tool finds the moments Jupiter comes back to the tropical longitude it held at your birth. Your natal Jupiter is computed first, as a tropical longitude, even if your chart is set to sidereal, so the dates are never shifted by the ayanamsa. Umbriel then scans forward from today for about 14.2 years (1.2 times Jupiter's geocentric period of 11.862 years in the code), sampling Jupiter's position in steps of at most 6 days. Wherever the position crosses your natal degree it halves the interval 40 times to pin the moment. Crossings are grouped into one return when they fall within a quarter of a period of each other, because Jupiter often retrogrades back over the degree and crosses it three times. The table lists each return dated from its first pass, every pass with its date and time, and marks a return as partial if a pass falls outside the window searched. Jupiter's position comes from the VSOP87D series, which the accuracy page reports within 2.5 arcseconds of NASA/JPL Horizons for Jupiter, Saturn, Uranus and Neptune over 1910 to 2044, and Jupiter's mean motion in the code is 0.0831 degrees a day, so a single crossing is dated to well under a day except close to a station, where Jupiter is nearly still and the crossing time is less sharp. The dates depend on your birth moment only through your natal Jupiter, which moves slowly, but the house it is in needs a birth time. The table shows the next return and the ones after it that fall in the window, not every return since birth.