Which ayanamsa is the default?
The current horoscope API uses Lahiri (Chitrapaksha) as the default ayanamsa for sidereal chart calculations.
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Calculation Method
How We Calculate a Vedic Kundli
A transparent overview of the current Kundli calculation pipeline—from birth details and astronomical positions to Lagna, houses, Moon sign, Vimshottari Dasha and derived chart analysis.
Swiss EphemerisLahiri ayanamsaBirth time + placeVimshottari DashaWhole-chart interpretation
Inputs
A Kundli begins with time and place
The birth-chart calculation uses date of birth, birth time and birthplace. The place is resolved to geographic coordinates and a time zone so the birth moment can be converted correctly for astronomical calculation.
DateSets the astronomical date for the birth moment.
Birth timeImportant for Lagna, houses and any factor that changes quickly through the day.
BirthplaceProvides latitude, longitude and time-zone context for the chart.
Astronomical Engine
Planetary positions and the sidereal zodiac
The horoscope API uses the Swiss Ephemeris for planetary calculations and uses Lahiri (Chitrapaksha) as the default ayanamsa for the sidereal zodiac. The result is then organized into the Vedic chart framework.
| Layer | What the current system calculates |
|---|---|
| Lagna | Ascendant sign and degree, with Nakshatra and Pada information where returned. |
| Navagraha | Nine graha positions placed into signs/houses, including degree information and analytical flags such as dignity, retrograde status and combustion where applicable. |
| 12 houses | House framework derived from the birth chart and Lagna for interpretation of life areas. |
| Moon sign | Chandra Rashi and Moon degree, used by several timing and transit modules. |
| Birth Panchang | Tithi, Nakshatra and Yoga at the birth moment are included in the broader chart output. |
Timing
How Vimshottari Dasha is connected to the chart
The Dasha module first generates the Kundli, then uses the Moon’s sidereal longitude from the birth chart to construct the Vimshottari Dasha sequence and the balance operating at birth. This keeps the Dasha timeline tied to the same Moon position used by the chart calculation.
Interpretation note: A Dasha is a timing framework. The quality of a period is not determined by the planet name alone; house ownership, placement, strength, combinations and transits matter.
Derived Analysis
Yogas, Doshas and deeper chart layers
After the base chart is created, separate analysis modules evaluate chart combinations. The current API includes classical Yoga/Dosha detection, divisional charts, Ashtakavarga and Shadbala-related outputs in addition to the core chart.
Yogas & DoshasDerived from planetary and house relationships. A detected combination is a flag for interpretation, not a complete prediction.
Divisional chartsThe API can derive Vargas such as D9 and D10 from the natal planetary positions for specialized analysis.
Strength systemsAdvanced sections such as Shadbala and Ashtakavarga add quantitative/contextual layers to the basic placement view.
Accuracy & Limits
What can change a Kundli result?
The most important user-side source of variation is birth time. A small time error can change the Ascendant degree and, near a sign boundary, the Lagna itself. Location/time-zone errors can also affect the birth moment used for the chart.
Astrology software can calculate positions consistently, but interpretation still requires judgment. Parashar Jyotisha therefore presents automated chart factors as structured information rather than claiming that one Yoga, Dosha or strength score decides a person’s life.
Responsible use: Kundli results are cultural, educational and interpretive tools. Medical, legal, financial and other high-stakes decisions need appropriate professional advice outside astrology.
Use the Tool
Generate a chart, then read the method alongside it
Common Questions
Kundli methodology FAQ
Which astronomical engine is used?
The current horoscope calculation stack uses Swiss Ephemeris for planetary positions.
Why does birth time matter so much?
The Ascendant moves continuously and the house framework depends on it. An uncertain birth time creates uncertainty in time-sensitive chart factors.
Does an automatic Yoga or Dosha result equal a prediction?
No. It identifies a chart combination. Interpretation should consider the whole chart, strength, cancellation/supporting factors, Dashas and transits.