How to Read a Birth Chart

A birth chart is a map of the sky at the moment and place you were born. To read it, go through four layers in order: planets, signs, houses and aspects, and start with the Sun, Moon and rising sign.

Build your birth chart first, so you can follow this guide with your own placements in front of you.

A note on what "reading" means here. Astrology is a tradition of interpretation, not a science. The positions in a chart are calculated, but what they mean is a matter of reading, and astrologers differ on details.

Planets are the "who" of the chart. Each one stands for a different part of a person's temperament and experience. In astrology, the Sun and the Moon are counted as planets too.

The ones to learn first:

• Sun. Core identity, drive, what a person is building toward.
• Moon. Emotional life, habits, what feels safe.
• Mercury. Thinking and communication.
• Venus. Values, taste, how a person relates to others.
• Mars. Energy, effort, how a person acts when they want something.
• Jupiter and Saturn. Growth and structure.
• Uranus, Neptune and Pluto. Slow planets that shape whole generations, so they say more about an era than about one person.

On a chart wheel each planet is drawn as a small symbol, so it helps to learn the symbols for the Sun and Moon first.

Don't try to read all ten at once. Add them one at a time.

A sign is the "how". It describes the style in which a planet is said to express itself. Mars in one sign is described differently from Mars in another, even though it is the same planet.

There are twelve signs. Each belongs to an element (fire, earth, air or water) and a modality (cardinal, fixed or mutable). Those two labels already tell you a lot: fire signs are usually described as energetic, earth signs as practical, air signs as mental, water signs as emotional. Cardinal signs start things, fixed signs hold steady, mutable signs adapt.

A short example. The Moon in a water sign is traditionally read as emotionally sensitive. The Moon in an earth sign is read as steadier and more practical about feelings. Neither is better. They are different descriptions of the same planet.

Two placements get their own pages, because they are the ones people look up most:

• What your moon sign means covers the Moon in each of the twelve signs.
• What is a rising sign explains the sign on the eastern horizon at your birth and how it is read.

The Sun's sign is the one you probably already know: it depends on your birth date and changes about once a month.

Houses are the "where". The chart is divided into twelve sections, and the house a planet sits in places it in an area of life: the first house is about self and appearance, the second about money and possessions, the fourth about home and family, the seventh about close partnerships, the tenth about career and public role, and so on.

Houses are drawn from the rising sign. The first house starts at the rising sign, and the others follow around the wheel. Because the rising sign changes about every two hours, the houses depend on an exact birth time and place. Two people born on the same day can have the same planets in the same signs and still have them in different houses.

Different astrologers use different house systems, which divide the wheel in different ways. Systems can disagree, sometimes by a whole house for a planet near a house edge. Focus on which house each planet is in, and on which houses are empty or crowded. Several planets in one house is usually read as a theme the person keeps returning to.

Aspects are the "how they interact". An aspect is a specific angle between two planets on the wheel. Planets that form an aspect are read as connected: they influence each other, either by working together or by creating friction.

Five aspects are used most:

• Conjunction (0 degrees). Two planets side by side. Their meanings blend and intensify.
• Sextile (60 degrees). A supportive link that offers an opportunity if you use it.
• Square (90 degrees). Tension that pushes toward action or change.
• Trine (120 degrees). An easy, natural flow between two planets.
• Opposition (180 degrees). Two planets across the wheel, pulling in different directions and asking for balance.

Aspects are measured with a margin, called an orb, because planets rarely sit at the exact angle. The closer the angle, the stronger the aspect is considered. An aspect at 119 degrees is close enough to count as a trine; the allowed orb varies between astrologers.

Aspects are the layer that makes a chart feel specific. Two people with the Moon in the same sign will read differently if one has a square from Saturn and the other a trine from Venus. They are also the layer that takes the most practice, so leave them for last.

Beginners get lost in the full wheel. A better order is to start small:

1. Sun sign. Read what it says about core identity.
2. Moon sign. Read what it says about emotional life.
3. Rising sign. Read what it says about how a person comes across and approaches new situations.

Together these three give a working outline of the chart, which is why astrologers call them the big three. Once they feel familiar, add the planet-by-planet layers: Mercury, Venus and Mars in their signs, then the houses, then the aspects.

A worked example, to show the order. This is an invented chart, not a real person's. Suppose the Sun is in Leo, the Moon in Pisces and the rising sign is Sagittarius.

• Planets: begin with the Sun and Moon.
• Signs: Leo is a fixed fire sign, usually described as warm and expressive. Pisces is a mutable water sign, described as sensitive and imaginative.
• Houses: with Sagittarius rising and a whole-sign house system, the first house is Sagittarius, so the Sun in Leo falls in the ninth house, a house of travel, study and belief. Your own chart uses the calculator's default house system, so the houses may be numbered differently.
• Aspects: look for a line between the Sun and the Moon. If they form a square, the reading would note a pull between a need for visibility and a need for softness.

That is the whole method: planet, sign, house, aspect, then a sentence that combines them.

You can still read the planetary signs in your chart without a birth time. In that mode the chart uses a noon reference, marks the result as unknown-time, and hides the rising sign (Ascendant), Midheaven (MC), houses, exact degrees, and aspects, so Steps 3 and 4 do not apply until you can add your birth time later. The calculator checks your entire local birth date for sign changes; if the Sun, the Moon, or another planet changes sign that day, it lists each possible sign instead of guessing one.

If you find your birth time later, from a birth certificate, hospital record or a relative, build your birth chart again to get houses and a rising sign.

Now put it into practice. Build your birth chart. The calculation is free and needs no sign-up, and the result comes with your big three and a short reading.