Chaturvimsamsa Chart Calculator (D24)

Cast your Chaturvimsamsa (D24), the twenty-fourth divisional chart of Vedic astrology - also called the Siddhamsa - from date, time, and place of birth. The tool computes your D24 Lagna with a birth-time-confidence check, every planet’s segment, deity, D24 sign and house, and renders the chart in North or South Indian style. Uses the sidereal Lahiri ayanamsa, the same engine as our Kundli, and conventional forward counting with the documented alternative disclosed.

100% private - the D24 calculation runs entirely in your browser. No birth data sent anywhere.

Enter birth details

Supports 1900 onwards for better calculation reliability.

Birth time matters MOST here: a D24 segment is 1 deg 15 min - the finest division on this site - so your D24 Lagna changes roughly every 5 minutes.

Related Tools

Quick facts

Chart / harmonicD24 (Chaturvimsamsa / Siddhamsa), the twenty-fourth divisional chart
Division size24 equal segments of 1 deg 15 min (1.25 deg) per sign
Start-sign ruleLeo for odd signs, Cancer for even signs (BPHS Ch. 6, 22-23)
Counting directionFORWARD both parities (convention); reverse-even fork disclosed, not computed
Presiding deitiesTwelve, cycling twice; even signs reversed from Bhima
Classically read forLearning (BPHS Ch. 7 varga-use verse); education/academics = later practice
D24 Lagna sensitivity~5 min of birth time per segment - the finest division on this site
Same-sign geometryEvery sign self-maps in exactly 2 of its 24 segments: one twelfth
NodesRahu/Ketu always share ONE D24 sign (opposite points have the same parity)
InputsDate, time, and place of birth
EngineMeeus VSOP87 + Lahiri ayanamsa; Rahu/Ketu = mean node (same engine as Kundli)
Privacy100% client-side; no birth data leaves your browser

What is the Chaturvimsamsa (D24) chart?

The Chaturvimsamsa - also spelled Chaturvimshamsha, and widely known as the Siddhamsa - is the twenty-fourth harmonic, one of the sixteen divisional charts (Shodasavarga) described in the Brihat Parashara Hora Shastra. Where the birth chart (D1) maps the whole life, each varga zooms into one domain, and the classical varga-use verse assigns the Chaturvimsamsa to learning.

Like every varga, the D24 is a derived chart: it takes each planet’s exact sidereal longitude from the birth chart and re-maps it. Nothing new is observed in the sky. Two things make the D24 stand out: it discards everything about the natal sign except its parity (all odd signs share one mapping, all even signs another), and its divisions are the finest on this site, which makes it the varga where birth-time accuracy matters most.

How the D24 is calculated

Each sign is divided into twenty-four segments of 1 deg 15 min. Per the verse, the distribution commences from Simh (Leo) for an odd sign and Kark (Cancer) for an even sign. This tool counts forward one sign per segment, so an odd sign runs Leo, Virgo, Libra... through two full cycles, and an even sign runs Cancer, Leo, Virgo... likewise. The deities cycle twice in the verse order for odd signs and reversed from Bhima for even signs:

Cycle positionOdd-sign deityEven-sign deity
1SkandBhima
2ParusdharMadan
3AnalGovinda
4VishwakarmaVrisha-Dwaja
5BhagAntaka
6MitrMaya
7MayaMitr
8AntakaBhag
9Vrisha-DwajaVishwakarma
10GovindaAnal
11MadanParusdhar
12BhimaSkand

The cycle repeats for segments 13-24 (position 1 again at segment 13). Worked example: a planet at 3 deg of Aries (odd) sits in segment 3, so its D24 sign is Libra - Leo, Virgo, Libra - with deity Anal. Each varga in the family carries its own rule: the Chaturthamsa walks the kendras, the Dwadasamsa counts forward from the sign itself, and the D24 counts forward from a parity-selected seed.

The counting-direction fork, disclosed

The verse pins the segment size, the two start signs, and the deity cycles - but it does not state whether the even-sign count runs forward or backward. The interpretation used by mainstream software, and by this tool, counts forward in both parities: odd signs Leo through Cancer twice, even signs Cancer through Gemini twice.

P.V.R. Narasimha Rao’s paper on the Siddhamsa (vedicastrologer.org, 2012) documents that convention and then argues against it: in his reading, the verse’s reversal instruction (“vilomena vicintayet”) applies to the signs as well as the deities, so even signs should count backward from Cancer - Cancer, Gemini, Taurus... - making the two mappings perfect mirrors. He calls that the correct Siddhamsa. Under his method a planet in an even sign generally lands in a different D24 sign than this tool shows.

We ship the conventional forward count because it is what today’s software ecosystem computes, and we name the alternative with its source rather than presenting either as settled. If you compare this tool against JHora - whose author is Narasimha Rao himself - note that its “calculation options recommended by author” preset applies his corrected methods, for the D24 the reverse-even count argued in the paper above, so a comparison lines up under the standard preset, not that one.

How the D24 is classically read

The Brihat Parashara Hora Shastra’s varga-use verse assigns the Chaturvimsamsa to learning - that translated word is the classical anchor. Practitioners in later tradition read the D24 for education, academics, and degrees; that is a gloss on the verse’s word rather than the verse’s own wording, so this page names it as later practice. The varga refines the birth chart rather than overriding it - the same relationship the Navamsa (D9) has with marriage significations and the Chaturthamsa (D4) has with fortunes.

All of this is descriptive tradition, not prediction. This page does not tell you how your studies will go, and offers no remedies, gemstones, or rituals - the classical text pins the domain and nothing here goes beyond naming it.

D24 Lagna and birth-time precision

A D24 segment is 1 deg 15 min, which the ascendant crosses in roughly 5 minutes of clock time at Indian latitudes - the fastest-moving varga Lagna on this site, twice as fast as the D12’s. If your recorded birth time is approximate, the D24 Lagna is the first thing that stops being trustworthy. Instead of quoting only the average, this tool computes your chart’s distance to the nearest D24 Lagna boundary in minutes and says so plainly.

Planet placements have the same fragility near a segment edge. This tool flags any planet within about 0.3 deg of a result-changing edge. On divisions this fine that band covers nearly half of all longitudes - the honest arithmetic of a 1.25-deg division, stated rather than tuned away. One edge is deliberately excluded: where an odd sign hands over to an even sign, the D24 sign is Cancer on both sides (the odd count ends where the even count begins), so nothing changes there and the flag correctly stays quiet.

What this version leaves out

This version computes the conventional-forward D24 chart, houses (whole-sign from the D24 Lagna), the deity cycles, and the birth-time-confidence checks. It does not compute the reverse-even variant (disclosed above), it does not interpret the chart, and it ships no predictions and no remedies.

Frequently Asked Questions

What is the Chaturvimsamsa (D24) chart?

The Chaturvimsamsa is the twenty-fourth divisional chart (varga) of Vedic astrology. Each 30-deg sign is divided into twenty-four segments of 1 deg 15 min, and every planet is re-mapped to a new sign based on which segment it occupies. The classical varga-use verse in the Brihat Parashara Hora Shastra assigns this chart to learning. It is read alongside the birth chart (D1), not instead of it.

Why is the D24 also called Siddhamsa?

Siddhamsa is the name P.V.R. Narasimha Rao uses for this chart - his paper on it is titled with that word, and the name is common in practice. The Brihat Parashara Hora Shastra translation this page consults calls the chart Chaturvimshahs and does not use the name Siddhamsa; we carry both so that either search finds the same tool.

How is the D24 chart calculated?

Per Brihat Parashara Hora Shastra Ch. 6, 22-23, the distribution commences from Leo for a planet in an odd sign and from Cancer for a planet in an even sign. This tool then counts FORWARD one sign per 1 deg 15 min segment through two zodiacal cycles - the conventional interpretation used by mainstream software. The verse itself does not state the counting direction, which is why a documented alternative exists (see the next question).

Is there more than one way to count the D24?

Yes, and we disclose it rather than hiding it. The convention - used by today's software and implemented here - counts forward from Leo (odd signs) and Cancer (even signs). P.V.R. Narasimha Rao's paper on the Siddhamsa argues the even signs should instead count BACKWARD from Cancer, reading the verse's reversal instruction as applying to the signs as well as the deities, and calls that the correct chart. This tool computes the conventional forward version and names Rao's position with its citation; it does not compute it.

Why are Rahu and Ketu always in the same sign in my D24?

Because of the chart's parity geometry, not a bug. Rahu and Ketu sit exactly 180 deg apart, which is six signs - and six signs away is always a sign of the SAME parity (odd/even), with the same degrees within the sign. Both nodes therefore get the same start sign and the same segment number, which is the same D24 sign, in every chart ever cast with this scheme. The same happens to any two planets in exact opposition.

Who are the deities of the chaturvimsamsas?

The Brihat Parashara Hora Shastra names twelve - Skand, Parusdhar, Anal, Vishwakarma, Bhag, Mitr, Maya, Antaka, Vrisha-Dwaja, Govinda, Madan and Bhima - repeating twice across the 24 segments of an odd sign, and reversed from Bhima (Bhima first, Skand last) twice for an even sign. This tool shows the deity for each planet's segment; it attaches no predictive meaning to them, because the classical text assigns the names without interpretation.

Why does exact birth time matter so much for the D24?

A D24 segment is 1 deg 15 min - the finest division this site ships. The ascendant crosses one in roughly 5 minutes of clock time at Indian latitudes, so even a small birth-time error can move the D24 Lagna by one or more signs. This tool reports how many minutes your entered time sits from the nearest D24 Lagna boundary, and flags any planet sitting within about 0.3 deg of a result-changing segment edge - on divisions this fine, that flag fires for nearly half of all placements, which is honest arithmetic rather than alarm.

Does this show the North Indian or South Indian chart style?

Both - use the North Indian (diamond) / South Indian (square) toggle above the chart; both draw the same D24 (Chaturvimsamsa) placements. In the North Indian format the houses are fixed with the Lagna at the top and the signs rotate; in the South Indian format the signs are fixed in the grid and the ascendant is marked in its box. Pick whichever regional format is more familiar.

Does this tool predict education, exam results, or degrees?

No. It computes the classical D24 chart and reports what traditional sources say the chart is consulted for - the varga-use verse assigns it to learning, and later practice reads it for education and academics. It makes no predictions about your studies or your life, it does not tell you what will happen to you, and it offers no remedies, gemstones, or rituals.

Sources

  • Parashara, Brihat Parashara Hora Shastra, Ch. 6, 22-23, for the segment size, the start signs and the deity cycles: “The Chaturvimshahs (l/24th part of a Rasi, or 1 deg 15’ each) distribution commences from Simh and Kark, respectively, for an odd and an even Rasi... Reverse these from Bhima twice to know the deities for the Chaturvimshahs in an even Rasi.” Ch. 7, 1-8 for the varga-use assignment (“learning from Chaturvimshahs”). Consulted through the English translation in the R. Santhanam lineage (full-text scan at archive.org, Parashara Hora Sastra, accessed 27 July 2026).
  • P.V.R. Narasimha Rao, “Correct Siddhamsa Chart of Pararsara” (title as printed; vedicastrologer.org, September 2012, accessed 27 July 2026), for the documented counting-direction fork: the paper records the conventional forward interpretation used by today’s software, argues for reverse-even counting as the correct reading, and is the source of the name Siddhamsa as used in the title of this page. This tool implements the conventional method and cites his position rather than computing it.
  • Parity: predicted D24 placements for two pinned fixtures are recorded in this repository’s evidence file before any external capture, and diffed against JHora under Traditional Lahiri with the mean node and the standard divisional preset (JHora’s author-recommended preset flips the D24 to reverse-even, so the preset is recorded with the capture). Exact segment cutoffs and the deity assignments are covered by our own exhaustive test matrix against the sources above.
  • N.C. Lahiri, Indian Astronomical Ephemeris (Rashtriya Panchang), for the sidereal Lahiri ayanamsa.
  • Jean Meeus, Astronomical Algorithms, 2nd ed., 1998 (VSOP87), for the planetary positions.

This page is the canonical surface for these terms: Chaturvimsamsa, Chaturvimshamsha, Siddhamsa, and D24 chart. They all refer to the twenty-fourth divisional chart described above.

Cultural / informational purposes only
Chaturvimsamsa results on this page are for cultural and informational purposes only. They describe a sidereal Vedic astrology reference frame, not predictions about your education, learning, or life, and are not a substitute for professional advice. Last updated: July 2026.