D60 Chart Calculator (Shashtiamsa)
A free D60 shashtiamsa chart calculator — each sign cut into sixty parts of exactly half a degree, every planet placed by its precise longitude.
The shashtiamsa is the sixty-fold division: each 30-degree sign split into sixty parts of 0 degrees 30 minutes. Half a degree divides a degree exactly twice, so no division is needed: double the degrees a body has travelled in its sign, drop the fraction, add one, and that is the part. Jagannatha Hora computes it from astronomical longitudes, under the in-app label D-60 shastiamsa.
Sources differ on where the sixty parts are counted from; this calculator counts from the occupied sign, as PVR Narasimha Rao reads it. Brihat Parashara Hora Shastra chapter 6 — double, divide by twelve, add one to the remainder — reads literally as counting from Aries. The D60 is the finest chart of the sixteen-fold Shodasavarga, though this engine draws the D81, D108 and D144 too.
Six D60 signs from one sample chart
Sixty rows per sign is too many to print, so here is the arithmetic instead, for a sample chart cast 1 January 1990, noon IST at Chennai — a fabricated date, nobody's birth. Each part comes from the doubling rule above; the sign is counted that many places on. Eight bodies, six distinct D60 signs.
| # | Body (D1 longitude) | Part -> D60 sign |
|---|---|---|
| 1 | Ascendant, Pisces 16.4685 deg | 33rd part -> Scorpio |
| 2 | Sun, Sagittarius 16.8657 deg | 34th part -> Virgo |
| 3 | Moon, Aquarius 6.4655 deg | 13th part -> Aquarius |
| 4 | Mars, Scorpio 16.1275 deg | 33rd part -> Cancer |
| 5 | Mercury, Capricorn 2.0133 deg | 5th part -> Taurus |
| 6 | Jupiter, Gemini 11.4557 deg | 23rd part -> Aries |
| Parts per sign | 60 | |
Mercury shows the method: 2.0133 doubled is 4.0266 — 4, plus one, is the 5th part, and the 5th sign from Capricorn is Taurus. The Moon wraps: its 13th part is the 13th sign from Aquarius, which is Aquarius again. Venus and Saturn take the 26th and 44th parts, into Aquarius and Cancer.
The heaviest weight in Shodasavarga
In Shodasavarga the D60 carries 4 of the 20 Vimsopaka points — ahead of the Rasi's 3.5 and the navamsa's 3, and eight times the 0.5 given to nine of the sixteen.
720 cells, against 108
Sixty parts across twelve signs make 720 distinct D60 cells around the zodiac, against the navamsa's 108 and the drekkana's 36. Charts minutes apart in birth time can fall in different shashtyamsas.
Every placement re-derivable
Counting from Aries and from the occupied sign give different signs for one longitude. This one counts from the occupied sign and prints the part number beside it, so placements can be checked by hand.
Common questions
What is the D60 chart in astrology?
The D60, or shashtiamsa, is the sixty-fold divisional chart: each sign split into sixty parts of half a degree, each planet re-placed into the sign its part points to. Classically it is the varga consulted for past-life karma and the fine-tuning of all matters.
How is the D60 chart calculated?
Double the degrees a planet has travelled in its sign, drop the fraction, add one — that is the part, 1 to 60. Count that many signs from the occupied sign, dropping twelves. At 2.0133 degrees of Capricorn that is the 5th part, and Taurus.
Is the D60 counted from Aries or from the occupied sign?
Both readings circulate. PVR Narasimha Rao counts from the sign the planet occupies, the convention used here; Brihat Parashara Hora Shastra chapter 6 reads literally as counting from Aries. The two coincide only for a planet in Aries.
Do I need my exact birth time?
Yes, more than for any coarser chart. One shashtiamsa spans half a degree, which the ascendant crosses in roughly two minutes on average — faster or slower with latitude and the rising sign — so a time rounded to five minutes can move the D60 ascendant two or three parts.