Free Astrology Calculator
Sidereal Birth Chart Calculator
Cast your birth chart in the sidereal zodiac used by Vedic astrology. Enter your birth details to see your Lagna, the nine grahas with their nakshatras and navamsa, and the chart in North or South Indian style.
Planets Today in the Sidereal Zodiac
Where the nine grahas stand now with the Lahiri ayanamsa, computed October 22, 2026 at 21:43 UTC. For the tropical positions, see planets today.
| Graha | Sidereal | Nakshatra |
|---|---|---|
| Sun | 5°16' Libra | Chitra pada 4 |
| Moon | 23°29' Aquarius | Purva Bhadrapada pada 2 |
| Mars | 19°40' Cancer | Ashlesha pada 1 |
| Mercury | 26°37' Libra | Vishakha pada 2 |
| Jupiter | 28°53' Cancer | Ashlesha pada 4 |
| Venus | 7°16' Libra | Swati pada 1 |
| Saturn | 15°39' Pisces | Uttara Bhadrapada pada 4 |
| Rahu | 2°19' Aquarius | Dhanishta pada 3 |
| Ketu | 2°19' Leo | Magha pada 1 |
Two Zodiacs, One Sky
Tropical and sidereal astrology look at the same planets at the same moment. They differ in where the circle of signs begins. The tropical zodiac begins Aries at the March equinox, the point where the Sun crosses the celestial equator heading north, so its signs are tied to the seasons and the light of the year. The sidereal zodiac begins Aries against the fixed stars, so its signs follow the constellations behind the planets.
About two thousand years ago the two starting points nearly coincided. The Earth's axis slowly wobbles, which carries the equinox backward through the stars by about one degree every 72 years, and today the two zodiacs sit roughly 24 degrees apart. A planet at 10 degrees Taurus in a tropical chart sits near 16 degrees Aries in a sidereal one.
Each frame answers its own question. The tropical zodiac describes a placement through the rhythm of the seasons; the sidereal zodiac describes it through the stars and the 27 lunar mansions that Indian astrology has refined for millennia. Selfgazer's charts use the tropical zodiac, and this calculator gives you the sidereal view beside it so you can read both with care.
The Ayanamsa
The gap between the two zodiacs is the ayanamsa. Lahiri, the ayanamsa of India's national calendar, is defined in the Indian Astronomical Ephemeris as 23°15'00.658" on March 21, 1956, which places the star Spica (Chitra) near 0 degrees Libra. This calculator reproduces that value to within a fifth of an arcsecond and agrees with the Swiss Ephemeris to within the same margin for every ayanamsa it offers, from 1850 to 2150.
| Year | Lahiri on January 1 |
|---|---|
| 2020 | 24°07'55" |
| 2021 | 24°08'46" |
| 2022 | 24°09'38" |
| 2023 | 24°10'32" |
| 2024 | 24°11'27" |
| 2025 | 24°12'23" |
| 2026 | 24°13'19" |
| 2027 | 24°14'14" |
| 2028 | 24°15'08" |
| 2029 | 24°16'01" |
| 2030 | 24°16'52" |
| 2031 | 24°17'41" |
| 2032 | 24°18'28" |
| 2033 | 24°19'14" |
| 2034 | 24°19'58" |
| 2035 | 24°20'43" |
Reading a Vedic Chart
- The Lagna, the sign rising in the east at birth, is the first house. With Whole Sign houses, each following sign is the next house.
- The nine grahas are the Sun, Moon, Mars, Mercury, Jupiter, Venus and Saturn, with Rahu and Ketu, the nodes of the Moon.
- Nakshatras divide the zodiac into 27 lunar mansions of 13°20'. The Moon's nakshatra at birth is central to a Vedic reading; find yours with the nakshatra calculator or browse all 27 nakshatras.
- The navamsa (D9) divides each sign into nine parts of 3°20', one per nakshatra pada. It is the most used of the divisional charts.
How Accurate Is It?
Tropical positions come from the engine behind every Selfgazer chart, held to the Swiss Ephemeris within half an arcminute. The ayanamsa is carried from its definition with the IAU 2006 precession and adds the nutation of the date, as the Swiss Ephemeris does, and sidereal positions agree with it within half an arcminute. Local time follows your birthplace's historical time zone rules. Read more in how Selfgazer calculates charts.
Sidereal Chart Questions
What Is the Difference Between a Sidereal and a Tropical Birth Chart?
Both use the same twelve signs and the same planets at the same moment. The tropical zodiac starts Aries at the March equinox, so the signs follow the seasons. The sidereal zodiac starts Aries against the background stars. The two starting points drift apart by about one degree every 72 years and are now about 24 degrees apart, so many placements fall one sign earlier in a sidereal chart.
Is a Vedic Birth Chart the Same as a Sidereal Chart?
A Vedic (Jyotish) chart is a sidereal chart read with the methods of Indian astrology: the Lagna and Whole Sign houses, the nine grahas including Rahu and Ketu, the 27 nakshatras, divisional charts such as the navamsa, and the dasha periods. Western sidereal astrologers use the same zodiac with other techniques.
What Is an Ayanamsa?
The ayanamsa is the angle between the start of the tropical zodiac and the start of the sidereal zodiac. Subtracting it from a tropical position gives the sidereal position. Traditions differ on where the sidereal zodiac begins, so there are several ayanamsas a degree or two apart.
Which Ayanamsa Should I Use?
Lahiri, also called Chitrapaksha, is the standard in India and the default in most Vedic software, so it is the default here. Krishnamurti is used with the KP system, Raman follows B. V. Raman's books, and Fagan-Bradley is the usual choice of Western sidereal astrologers.
What Is the Lahiri Ayanamsa This Year?
The table on this page lists the Lahiri ayanamsa on January 1 of each year from 2020 to 2035. It grows by about 50 arcseconds a year as the equinox precesses, and the value at your own birth appears with your chart.
Why Does Vedic Astrology Use Whole Sign Houses?
In the classical Indian method each sign is one house, counted from the sign of the Lagna (Ascendant). It is the older house method in both traditions. Placidus is offered for readers who follow the KP system or want to compare.
Can I Make a Vedic Chart Without a Birth Time?
Yes, with limits. The planets are placed for local noon and the chart is drawn from the Moon's sign (Chandra Lagna), a traditional way to read a chart without a time. The Lagna, houses and an exact Moon need the birth time.