Planet positions
Every position is computed with Swiss Ephemeris (version 2.10.03), from the data files bundled with the app. Positions are geocentric and apparent.
Methodology
How Swarn Siddhi computes charts and timings
Every chart, panchang and muhurat on this site comes from one engine with the settings below. They are listed so that you can reproduce a value, or see why another calendar prints a different one. This page does not say which tradition is right.
Zodiac and ayanamsa
The sidereal zodiac with the Lahiri (Chitrapaksha) ayanamsa. On 26 October 2026 the Lahiri ayanamsa is 24°14′02″; over the last fifty years it grew by 50.1″ a year on average, and it is the whole difference between a tropical (Western) and a sidereal sign.
Rahu and Ketu
Rahu is the mean node; Ketu is always exactly opposite, 180° away.
Where tropical positions appear
Only where a page says so, such as the sun sign calculator, which prints both zodiacs side by side. Every kundli, panchang and muhurat is sidereal.
Lagna
The sidereal degree rising on the eastern horizon at the birth time and place. The lagna changes sign roughly every two hours, which is why the birth time matters most here.
Houses
Whole-sign houses: the lagna's sign is the first house, the next sign the second, and so on.
Nakshatras
Twenty-seven equal parts of the zodiac of 13°20′ each, with four padas of 3°20′.
Vimshottari dasha
From the Moon's nakshatra. The balance at birth follows the part of the nakshatra the Moon has yet to cross, and the mahadashas are stepped in calendar years.
The birth time zone
The birthplace's IANA time zone, found from its coordinates, with the rules in force on that date: past changes and other countries' daylight saving included.
Sunrise and sunset
The moment the upper edge of the Sun touches the horizon, with standard atmospheric refraction, for the place's latitude and longitude at sea level.
The Vedic day
From one sunrise to the next. A time after midnight still belongs to the previous date's night, and the pages print the date beside such a time.
The tithi of a day
The panchang names each day by the tithi running at its sunrise (udaya tithi), and prints when that tithi ends.
A festival's date
Each festival by its own classical rule: the part of the day its tithi must hold. Some examples:
- Raksha Bandhan: at sunrise
- Narak Chaturdashi: in Arunodaya, the four ghatis before sunrise
- Ganesh Chaturthi: in Madhyahna, the middle fifth of the day
- Dussehra (Vijayadashami): in Aparahna, the fourth fifth of the day
- Diwali: in Pradosh, the evening after sunset
- Kali Puja: in Nishita, around midnight
- Karwa Chauth: at moonrise
When a tithi touches two days, that rule decides which one keeps the festival.
Muhurtas and kaals
Rahu Kaal, Yamaganda and Gulika: the weekday's eighth of the daylight (sunrise to sunset). Choghadiya: eight parts of the day and eight of the night. Abhijit: the eighth of the day's fifteen muhurtas (none on a Wednesday). Pradosh: a fifth of the night. Nishita: the eighth of the night's fifteen muhurtas. Every time is cut to the minute, never rounded.
City pages
The panchang, Rahu Kaal, choghadiya and festival city pages cover 84 cities (75 in India). Each city is one fixed point: its latitude and longitude, printed on its pages.
Time zones
Each city's IANA time zone was resolved from its coordinates, and a test re-checks every one. Outside India, daylight saving follows that zone's own rules.
Your own place
A birthplace or city you search for is turned into coordinates, and its time zone is found from those coordinates.
Today, for example
On 26 October 2026 sunrise is 5:37 AM in Kolkata, 6:28 AM in New Delhi and 6:36 AM in Mumbai: 59 minutes apart on the same clock. Each degree of longitude is four minutes of time, so every timing moves with the city.
The definition of sunrise
On 26 October 2026 in New Delhi: the Sun's upper edge with refraction, 06:28:35; the centre of the disc with refraction, 06:29:50; the centre without refraction, 06:32:43. The definition alone moves sunrise by about 4 minutes, and every period counted from sunrise moves with it.
The place
A city centre against your own neighbourhood, or two calendars using different coordinates for one city: each degree further east is four minutes earlier.
The ayanamsa
An ayanamsa other than Lahiri shifts every sidereal position by the same small angle. A planet or lagna near the edge of a sign or nakshatra can change sign or nakshatra, and the moment a lagna begins moves too.
The festival's rule
Which part of the day the tithi must hold, and which day keeps the festival when the tithi touches two: this is where calendars differ most. In a year when it happens, the festival's page says why for that year (for example Diwali).
Period lengths and lagna tables
Some calendars give a period such as pradosh a fixed length; here pradosh is a fifth of the night. Some carry one lagna table through the whole night; here a lagna's time is found from the rising sign itself.
Cutting to the minute
Every time here is truncated to the minute; a calendar that rounds can show one minute later.
So a difference of a minute or two is normal. A difference of a day usually comes from a different festival rule, a different time zone or a different city. If a value still looks wrong after that, write to us on the contact page with the page, the city and what you expected.
Calculation and interpretation are separate
Every number above is a calculation. Meanings, scores and muhurat rules come from traditional Jyotish, not from scientific evidence. AI only puts computed values into words; it does not build the chart. How Swarn Siddhi works sets out these layers one by one.
Not advice
No result is medical, legal, financial or mental-health advice.
Methodology: questions
Which ayanamsa does Swarn Siddhi use?
The Lahiri (Chitrapaksha) ayanamsa, with Swiss Ephemeris. On 26 October 2026 it is 24°14′.
How is sunrise defined?
The Sun's upper edge on the horizon, with standard refraction, for the place's latitude and longitude at sea level.
Why does another panchang show a different time?
A different definition of sunrise (about 4 minutes in New Delhi today on its own), different coordinates for the city, another ayanamsa, another festival rule, a fixed period length or rounding instead of truncating.
How is the tithi of a day decided?
By the tithi running at sunrise (udaya tithi). Festivals follow their own rule: the part of the day the tithi must hold.
Which time zone is used for a birth chart?
The birthplace's IANA time zone, found from its coordinates, with the rules in force on the birth date.