A birth chart needs a date, a time standard, and a place. A sidereal rashi chart then places the Sun, Moon, and planets in twelve equal zodiac signs. The ayanamsha states which sidereal reference is used. A different ayanamsha setting can produce a different chart from the same birth record.
Start with the Lagna
The Lagna is the sign rising at the eastern horizon at the recorded birth time and place. It changes quickly, so a missing or approximate clock time makes it unreliable. In a Whole Sign chart the entire Lagna sign is the first house, the next sign is the second house, and the count continues through all twelve signs. When the time is missing, the calculator withholds Lagna and houses rather than inventing them from a noon sample.
Read the South Indian layout
In the South Indian diagram the signs stay in fixed cells. Pisces, Aries, Taurus, and Gemini fill the top row from left to right. The sequence proceeds clockwise around the outside of a four-by-four square. The middle four cells are blank. A Lagna marker moves from one sign cell to another depending on the calculated Ascendant. Small labels inside each cell abbreviate the grahas; the adjacent table spells out their names, exact displayed sign degrees, and houses.
| Rashi | One of twelve sidereal signs, each spanning exactly 30° of longitude in this calculation. |
|---|---|
| Lagna | The sidereal Ascendant sign, calculated from the birth time and geographic coordinates. |
| Grahas | The traditional seven shown here are Sun, Moon, Mars, Mercury, Jupiter, Venus, and Saturn. |
| Rahu and Ketu | The mean north and south lunar nodes. Ketu is placed 180° opposite Rahu. Some software instead uses true nodes; the two methods differ. |
| Nakshatra | One of 27 equal lunar mansion segments, each 13°20′ long, beginning at sidereal Aries 0° in this page’s convention. |
| Pada | One of four equal subdivisions of a nakshatra, each 3°20′ long. |
Why your result may differ from another site
First compare the recorded local time and historical UTC offset. A 30-minute offset error moves the Moon and angles, and even a smaller change can matter when a point is near a sign or nakshatra boundary. Next compare the ayanamsha, node method, ephemeris, and house convention. A Lahiri result and another sidereal convention are not interchangeable; mean Rahu and true Rahu need not occupy exactly the same longitude.
This site uses a published Lahiri reference value and a precession/nutation approximation applied to Astronomy Engine’s planetary positions. It does not run the Swiss Ephemeris. Small numeric differences are expected, and close boundary assignments deserve a specialist check. The Astronomy Engine API documents the local astronomical position calculations used here.
What the chart leaves out
A rashi table is a position reference, not a complete Jyotish reading. Divisional charts such as the Navamsha, planetary periods, yogas, dignity, strength, and interpretive schools require additional conventions and calculations. This page provides no score, prediction, or claim about life outcomes. It also limits local birth dates to 1800–2100 and does not research historical time zones for you. Record the method and inputs whenever you save or compare a result.
Calculate a Vedic rashi chart →
What this Vedic birth chart calculates
This page starts with an astronomical sky calculation at the entered UTC instant, then converts its apparent geocentric tropical longitudes to a sidereal zodiac with an approximate Lahiri ayanamsha. The rashi diagram follows the South Indian fixed-sign layout. The sign containing the sidereal Ascendant is marked Lagna, and Whole Sign houses count from that sign. Seven classical grahas and the mean lunar nodes, Rahu and Ketu, appear in the position table.
If the birth time is known, the Moon’s sidereal longitude also selects one of 27 equal nakshatras and one of four padas within it. If the time is unknown, the page uses a local-noon sample only for the remaining planetary longitudes and withholds Moon, nakshatra, Lagna, and houses. An uncertain historical UTC offset can change the result, especially near a boundary.
The calculation uses Astronomy Engine 2.1.19 and a separately coded Lahiri approximation. It is not a Swiss Ephemeris calculation and cannot claim numerical parity with professional Jyotish software. This tool does not calculate vargas, dashas, yogas, strength scores, or predictive judgements.