Setting the ayanamsa: Lahiri, KP and Raman

Every number on this page is a real API answer. The chart is the one the docs use: John Doe, born Aug 15, 1990, 10:30 AM, New York. The examples look at his ascendant, the sign rising in the east at birth. They also look at his planets and their nakshatras, the 27 star groups of Vedic astrology.

What is an ayanamsa?

An ayanamsa is the number of degrees between the Western zodiac and the Vedic one. The Western (tropical) zodiac is tied to the seasons. The Vedic (sidereal) zodiac is tied to the stars. A slow wobble of the Earth's axis pulls the two apart by about 50 arc seconds a year.

The slow wobble is called precession. An arc minute is 1/60 of a degree, and an arc second is 1/60 of an arc minute. The API returns only Vedic positions, on the sidereal zodiac. To get them, it takes the ayanamsa off each Western position. Each response gives the value it used in meta.ayanamsa_value, in degrees. To see what this means for a user’s Sun sign, read Vedic vs Western astrology. The ayanamsa glossary entry has a short definition.

Which ayanamsas can I choose?

You can choose from eight ayanamsas. Lahiri is the default. KP and Raman are the most asked for after it. Yukteshwar, Fagan-Bradley, J. N. Bhasin and Usha-Shashi are fixed distances from Lahiri too. True Chitra follows the star Spica itself. Send the code, such as "ayanamsa": "kp", with the birth details. Every response names it in meta.ayanamsa.

• lahiri Lahiri, the default

  At John Doe’s birth: 23.7261°

  Gap from Lahiri: None: the starting point

• kp Krishnamurti, used in KP astrology

  At John Doe’s birth: 23.6292°

  Gap from Lahiri: 5.8 arc minutes smaller (0.10°)

• raman B. V. Raman's

  At John Doe’s birth: 22.2798°

  Gap from Lahiri: 86.8 arc minutes smaller (1.45°)

• yukteshwar Sri Yukteshwar's

  At John Doe’s birth: 22.3478°

  Gap from Lahiri: 82.7 arc minutes smaller (1.38°)

• fagan_bradley Fagan-Bradley, the Western sidereal zodiac

  At John Doe’s birth: 24.6093°

  Gap from Lahiri: 53.0 arc minutes larger (0.88°)

• jn_bhasin J. N. Bhasin's

  At John Doe’s birth: 22.6311°

  Gap from Lahiri: 65.7 arc minutes smaller (1.09°)

• ushashashi Usha-Shashi

  At John Doe’s birth: 19.9265°

  Gap from Lahiri: 228.0 arc minutes smaller (3.80°)

• true_chitra True Chitrapaksha, which keeps the star Spica at 180°

  At John Doe’s birth: 23.7077°

  Gap from Lahiri: 1.1 arc minutes smaller (0.02°)

Send the field with the birth details. Here is John Doe’s request to POST /v1/planets with the KP ayanamsa:

{
  "year": 1990,
  "month": 8,
  "day": 15,
  "hour": 10,
  "minute": 30,
  "second": 0,
  "latitude": 40.7128,
  "longitude": -74.006,
  "timezone": "America/New_York",
  "ayanamsa": "kp"
}

Yukteshwar, Fagan-Bradley, J. N. Bhasin and Usha-Shashi stay the same distance from Lahiri on every date, like KP and Raman. True Chitra keeps the star Spica (Chitra) at exactly 180°, so it follows the star itself, and its gap from Lahiri drifts by about 14 arc seconds across the API’s date range. The rest of this page compares the three most asked for: Lahiri, KP and Raman.

The choice carries through the whole answer. Transits and sade sati for that chart use the same ayanamsa, and so do forecasts. Transits are where the planets are on a given day. Sade sati is Saturn’s long pass over the Moon sign.

How far apart are Lahiri, KP and Raman?

At John Doe's birth moment, Lahiri is 23.7261 degrees, KP is 23.6292 and Raman is 22.2798. So KP is 5.8 arc minutes smaller than Lahiri, and Raman is 86.8 arc minutes smaller. An arc minute is 1/60 of a degree. The API keeps both gaps the same on every date.

How we measured: on Nov 2, 2026, we sent John Doe’s birth details to POST /v1/planets three times. Each call used a different ayanamsa. The values are meta.ayanamsa_value from those answers. Then we changed only the year, to 1900, 2026 and 2100. Both gaps stayed the same each time. The API moves all three ayanamsas by the same yearly drift, so the gaps never grow.

Other software sometimes uses a slightly different value under the KP name (KP-01). A point near the edge of a sub, a small slice of a nakshatra, can then get a different sub lord. So compare KP charts by meta.ayanamsa_value, not by the name alone.

What changes in a chart?

Compared with Lahiri, every planet and the ascendant move forward by the gap. Most stay in the same sign and nakshatra (star group). A point near the end of one can cross into the next. In John Doe's chart, Raman moves the Sun from Cancer into Leo. KP moves only the ascendant, into its next pada (quarter of a nakshatra).

The table shows every point of John Doe’s chart that changes its sign, nakshatra, pada or house. Bold marks what changed from Lahiri.

• Ascendant

  Lahiri

  Virgo 19.93°Hast, pada 3House 1

  KP

  Virgo 20.03°Hast, pada 4House 1

  Raman

  Virgo 21.38°Hast, pada 4House 1

• Sun

  Lahiri

  Cancer 28.78°Ashlesha, pada 4House 11

  KP

  Cancer 28.87°Ashlesha, pada 4House 11

  Raman

  Leo 0.22°Magha, pada 1House 12

• Mercury

  Lahiri

  Leo 25.75°Purva Phalguni, pada 4House 12

  KP

  Leo 25.85°Purva Phalguni, pada 4House 12

  Raman

  Leo 27.20°Uttara Phalguni, pada 1House 12

• Jupiter

  Lahiri

  Cancer 5.69°Pushya, pada 1House 11

  KP

  Cancer 5.79°Pushya, pada 1House 11

  Raman

  Cancer 7.14°Pushya, pada 2House 11

• Saturn

  Lahiri

  Sagittarius 26.13°Purva Ashadha, pada 4House 4

  KP

  Sagittarius 26.22°Purva Ashadha, pada 4House 4

  Raman

  Sagittarius 27.57°Uttara Ashadha, pada 1House 4

The Moon, Mars, Venus, Rahu and Ketu keep their sign, nakshatra, pada and house with all three.

A sign change carries into everything built on the chart. Houses are whole signs counted from the ascendant (CH-06). So with Raman, John Doe's Sun moves from house 11 to house 12. In Leo, the Sun also stands in its mulatrikona, a favored stretch of its own sign (CH-04). Its degree in the sign falls from 28.78 to 0.22. So it is no longer his atmakaraka, the planet with the highest degree in its sign (JM-01).

The written reading follows the chart. Of the 7 blocks in John Doe’s Sun reading, 5 get a new title with Raman. With KP, none change.

• “Sun · friend” becomes “Sun · mulatrikona”
• “Sun in Cancer” becomes “Sun in Leo”
• “Sun in the 11th house” becomes “Sun in the 12th house”
• “Lord of the 12th (Sun) in the 11th house” becomes “Lord of the 12th (Sun) in the 12th house”
• “Sun · Atmakaraka” becomes “Sun · Darakaraka”

Vimshottari dasha dates move even when no sign changes. A dasha is a planet’s period in this 120-year cycle. The Moon stays in Mrigashira with all three, so Mars still runs John Doe's first period (DA-02). But the Moon's place inside Mrigashira sets how much of that period was left at birth (DA-03). So every later date shifts. His Jupiter period ends on Dec 20, 2030 with Lahiri. With KP it ends on Dec 2, 2030, and with Raman on Mar 18, 2030.

How can I spot a planet near an edge?

Read degree_in_sign for each planet and the ascendant in a Lahiri chart. Above 28.55, the point sits in the next sign with Raman. Above 29.90, it moves with KP too. The same gap applies at the end of a nakshatra or a pada. To see every effect, call again with the other ayanamsa.

1. Call POST /v1/planets with the birth details. Leave out ayanamsa to get Lahiri.
2. Read degree_in_sign for the ascendant and each planet.
3. Flag any point above 28.55. With Raman, it falls in the next sign. Above 29.90, it moves with KP as well.
4. For the full picture, call again with "ayanamsa": "raman". Compare sign, nakshatra and pada, and match points by name. Each check is one more call on your plan.

In John Doe’s chart, the Sun is above 28.55, at 28.78. A nakshatra is 13°20′ wide and a pada 3°20′, so the same gap moves points across their edges too. That is how Mercury and Saturn change nakshatra with Raman while staying in their signs.

One chart shows what can move. To see how often it moves, we sent one birth for every day of 1990 with all three ayanamsas. The counts are in Lahiri, KP or Raman: which should your app use?

Why is Lahiri the default?

Lahiri is the default because it is the ayanamsa used most in India. It is named after N. C. Lahiri of India's Calendar Reform Committee, set up in 1952. Calendar calls that take no birth details, such as GET /v1/panchang/daily, always use Lahiri. Their answers say so in meta.ayanamsa.

Lahiri is the ayanamsa used most in India. N. C. Lahiri was member secretary of India’s Calendar Reform Committee. The API reference describes lahiri as the Lahiri, or Chitrapaksha, ayanamsa used by the Government of India.

Calls that take no birth details have no ayanamsa field. Examples are the daily panchang (the Hindu calendar for a day) and GET /v1/festivals. They always use Lahiri. On Nov 2, 2026, we sent ayanamsa=raman to GET /v1/panchang/daily anyway. Its meta.ayanamsa still said lahiri. So a Lahiri chart and the calendar calls use the same zodiac.

How do I choose an ayanamsa?

Send nothing, and you get Lahiri, the default. Send kp for users of KP astrology, and call POST /v1/kp for its house cusps and sub lords. Send raman for users who follow B. V. Raman's books. The other five suit users who already follow them. If you offer a choice, show the one you used beside each chart.

• Kundli matching and other calls about two people need the same ayanamsa for both charts. If not, they return a 422 error.
• POST /v1/kp always uses the Krishnamurti value and ignores the ayanamsa field. It also uses Placidus house cusps, another way to draw houses (KP-04). So do not mix its house numbers with those from other endpoints. Read more about KP astrology.
• Show the ayanamsa you used near the chart, such as “Lahiri ayanamsa”. A user who compares your chart with another app can then see why a planet sits somewhere else.

Which rules cover the ayanamsa?

Rule KP-01 in the rulebook defines the Krishnamurti ayanamsa. It also warns that other software may use a slightly different KP value. KP-04 keeps Placidus cusps inside the KP endpoint. A shift reaches other rules through the positions. They are CH-06 for houses, CH-04 for mulatrikona, JM-01 for the atmakaraka, and DA-02 and DA-03 for dashas.

• KP-01: The Krishnamurti ayanamsa
• KP-04: Placidus cusps, in this system only
• CH-06: Houses are whole-sign, counted from the ascendant
• CH-04: Mulatrikona signs
• JM-01: The seven chara karakas
• DA-02: Which lord runs first
• DA-03: The balance at birth is measured by time

The Lahiri default is stated in the API reference, on the ayanamsa field of the birth details. Browse every rule in the rulebook.