What Is Thai Astrology? A Plain-English Guide

Last updated: 8 October 2026

Thai astrology, called horasat in Thailand, is a traditional system of birth charts. It places the planets in a sidereal zodiac, calculated with the Suriyayatra calendar, and its charts include Rahu, Ketu and Uranus alongside the Sun, Moon and five planets. It draws on Indian astrology, in the Hindu and Brahmin tradition, mixed with Chinese influences, and it developed its own methods in Thailand. This guide explains how a Thai chart is made and what its parts mean. For a comparison with Western charts, see Thai vs Western astrology.

Thai zodiac animals are a different thing

If you searched for your Thai zodiac sign, you may be looking for your animal. Thailand uses a 12-year cycle of animals, with the Naga in place of the dragon. The animal depends on your year of birth. That is not a birth chart. A birth chart uses your date, time and place of birth to place the planets in 12 signs. This guide is about the chart.

How a Thai birth chart is made

A Thai chart starts from three facts: the date, the time and the place of your birth. From these, an astrologer works out four things.

• Your Thai weekday. The day is counted from sunrise, not from midnight.
• The planets in the signs. Positions come from the Suriyayatra calendar, the traditional Thai astronomical calendar. They are placed in the sidereal zodiac.
• The ascendant. Called Lakkhana in Thai, it is the sign rising on the eastern horizon at your birth. It sets the starting point of your houses. In our charts it comes from the ordinary Antonati method, a fixed table of rising times that does not change with latitude.
• The 12 houses. Each sign, counted from the ascendant, is one house. This is called the whole-sign system.

The sidereal zodiac and the Suriyayatra calendar

The sidereal zodiac is measured against the fixed stars. The Western tropical zodiac is measured from the spring equinox. Today the two are about 24° apart, so a Thai chart often puts a planet in the sign before the one you know from Western astrology. The full explanation, with a side-by-side table, is in Thai vs Western astrology.

An example chart

This chart is for a person born in London on 1 July 1985 at 12:00, British Summer Time. The person is made up for this guide, and the positions were calculated for it. Because the ascendant is in Virgo, Virgo is the 1st house, Libra the 2nd, and so on.

Born at 12:00, after local sunrise at 04:47, this person counts as born on a Monday. Once you know which house a planet is in, you look up what that house covers. The table of the 12 houses is further down this page.

The ten bodies in a Thai chart

A Thai chart numbers its bodies. The numbers are 1 Sun, 2 Moon, 3 Mars, 4 Mercury, 5 Jupiter, 6 Venus, 7 Saturn, 8 Rahu and 9 Ketu, with 0 for Uranus. Thai astrology does not use Neptune or Pluto. The Sun, Moon and five planets are the same bodies as in Western astrology. Three of the ten need more explanation.

One more difference: in Thai astrology, Rahu rules Aquarius. In our example chart, Rahu is in Aries 21°16′ and Ketu is in Capricorn 15°23′. They are not opposite each other.

The 12 houses

A house is one of 12 areas of life in a chart. Each house has a Thai name, shown here in the standard romanised spelling.

Your weekday of birth

Thai astrology gives every person a day ruler: the planet that rules the weekday of birth. Because the Thai day starts at sunrise, someone born in the early hours before sunrise counts as born on the previous weekday. People born on Wednesday night are given Rahu as their day ruler.

In the example chart, the person was born at 12:00 and sunrise was at 04:47, so the weekday is Monday.

How people in Thailand use astrology

In Thailand, many people consult an astrologer when weighing a decision, including when to begin something. We take the same view. A chart is a way to look at tendencies and timing, to support your own decisions.

Thai astrology also reads timing. The Outlook, called Duang Chon, compares today's planet positions with your birth chart to show how a period may look.

Is Thai astrology accurate?

Astrology is a traditional practice, not a science. We do not offer a measure of accuracy and we do not cite studies. Thai astrology gives you a framework for looking at tendencies and timing in your life. It does not predict what will happen. What you do with it is your choice.

Thai and Western, side by side

If you already know your Western chart, expect some differences. The two systems start their zodiac from different points, and they use different bodies. In the example chart, the Sun is in Cancer in the Western chart and in Gemini in the Thai chart. Our guide Thai vs Western astrology shows where the two part, step by step.

A Thai chart in your reading

Our Birth Chart + 3 Questions reading gives you your Thai birth chart with a key to every symbol, so you can learn to read it yourself. Your Western chart comes with it, and so do the points where the two systems agree and where they differ. Birth Chart + 6-Month Outlook adds the timing of the next six months. Where a Thai term has no good English equivalent, we keep the Thai word and explain it where it appears. These readings need your date, time and place of birth.

See the readings with a Thai birth chart

Common questions

Where to go next

To see how Thai and Western charts differ, read Thai vs Western astrology. To see how our readings work, go to Horaa House.

Choose a reading

Readings describe tendencies and timing, to support your own decisions. They do not guarantee any outcome.