Reading Your Birth Chart, One Layer at a Time
A birth chart maps the sky when you were born. Learn the six parts it is built from: rising sign, Moon sign, elements, modalities, aspects and retrogrades.
A birth chart, or natal chart, is a map of the sky at the exact moment and place someone was born. It is built from four layers: the signs, the planets in them, the houses they fall into, and the angles between them.
The order most readings follow
- Start with the big three. Sun for direction, Moon sign for needs, rising sign for approach.
- Check the balance. Count the elements and modalities across the whole chart before reading any single placement.
- Place the planets. Each planet lands in a sign and a house.
- Join them up. The aspects show which functions cooperate and which pull apart.
- Then add timing. Transits and retrogrades come last, not first - today's moon phase and zodiac season are the quickest way in.
Explore every part of the chart
Six guides covering the concepts the rest of the library keeps referring to.
Rising sign
Your rising sign, or Ascendant, is the zodiac sign that was climbing over the eastern horizon at the exact moment and place you were born. It...
Read the guideMoon sign
Your Moon sign is the zodiac sign the Moon was passing through at your birth. The Moon moves faster than any other body in the chart - roughly one...
Read the guideThe four elements
Astrology sorts the twelve zodiac signs into four elements - Fire, Earth, Air and Water - with three signs each. The element describes how a...
Read the guideCardinal, Fixed and Mutable Modalities
Modality sorts the twelve zodiac signs into three groups of four: Cardinal signs start things, Fixed signs sustain them, and Mutable signs adapt...
Read the guideAstrological aspects
An aspect is the angle between two planets measured around the chart wheel. Five angles are treated as major - conjunction, sextile, square, trine...
Read the guideSign cusps
A cusp is the boundary where one zodiac sign ends and the next begins. The Sun does not change sign at midnight on a fixed date - the exact moment...
Read the guideEclipses
An eclipse is a new or full moon that happens close to one of the lunar nodes, the two points where the Moon's orbit crosses Earth's path around...
Read the guideRetrogrades
A planet is retrograde when it appears to move backwards through the zodiac as seen from Earth. Nothing actually reverses - it is a trick of...
Read the guidePut the guides into practice
Calculate a chart, check the current sky, compare placements, or inspect the calendar behind a transit.
Birth chart calculator
Enter a birth date, local time, UTC offset and coordinates to calculate the Big Three, ten tropical placements, Whole Sign houses and major...
Open the toolCurrent planet positions
This live table gives the geocentric tropical longitude of the Sun, Moon and eight planets for the current UTC time, including apparent...
Open the toolAstrology event calendar
This calendar tracks exact quarter Moon phases and the moments when the Sun enters a new tropical zodiac sign during the next 45 days.
Open the toolMoon phase calendar
The 30-day table follows the Moon at noon UTC each day, showing its tropical sign, degree, named phase, illumination and waxing or waning direction.
Open the toolChinese zodiac compatibility
Choose two animal signs to see whether they share a traditional trine, form one of the six clash pairs, or sit outside those two named patterns.
Open the toolSynastry placement comparison
Select five personal placements for each person. The tool compares same-sign matches, shared elements and shared modalities, then points to...
Open the toolHouse system comparison
House systems divide the same chart in different ways. This comparison shows how four common systems define cusps and why a planet can change...
Open the toolCommon questions
What is a birth chart?
A birth chart, or natal chart, is a map of the sky at the exact moment and place someone was born. It is built from four layers: the signs, the planets in them, the houses they fall into, and the angles between them.
What do you need to calculate one?
Three things: your birth date, your birth time and your birth place. The date sets the planets, the time sets the rising sign and the houses, and the place fixes the horizon.
Do you need an exact birth time?
For the Sun sign, no. For the rising sign and the houses, yes - the Ascendant moves through all twelve signs every 24 hours, so an unknown time leaves several possible charts.
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Astrology is a cultural and symbolic practice, not a scientific method for predicting events. Our guides describe traditions accurately while keeping agency with the reader.
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