Understand
What is a birth chart?
Your birth chart is the exact snapshot of the sky at the moment and place you were born. A unique configuration that will never happen again, and that draws the portrait of your resources.
A snapshot of the sky
At the moment of your first breath, each planet occupied a precise position on the band of the zodiac, and one sign was rising on the eastern horizon: your Ascendant. The birth chart, also called a natal chart or chart wheel, is the drawing of that configuration, seen from the place of your birth. That is why three pieces of data are needed to calculate it: the date, the time and the place.
The three layers of the chart
The planets are the actors: the Sun (your identity), the Moon (your emotions), Mercury (your thinking), Venus (the way you love), Mars (your energy), then Jupiter, Saturn, Uranus, Neptune and Pluto, joined by sensitive points such as the North Node, Chiron or Lilith.
The signs are the costumes: they say how each planet expresses itself. A Moon in Aries reacts fast and hard; a Moon in Taurus seeks stability.
The houses are the settings: they say where, in which area of life, each planet acts. Mars in the 10th house fights for a career, Mars in the 7th house within the couple.
The aspects: the inner dialogue
The planets form angles with one another, called aspects. A trine (120°) is a natural alliance, a square (90°) a tension that pushes you to act, a conjunction (0°) a fusion. These aspects describe how your different facets cooperate or jostle one another: this is where the chart becomes truly personal.
How is a chart calculated?
The calculation relies on ephemerides, that is, the astronomical positions of the planets, converted into longitudes on the tropical zodiac. The local time is first converted to universal time using the time zone of the place (with its historical rules, daylight saving included), then the Ascendant and the houses are derived from the local sidereal time and the latitude. On this site, these calculations are made with arc-minute precision: calculate your chart for free.
What is a birth chart for?
To know yourself better: spotting your natural strengths, understanding your contradictions, identifying the areas where you grow, and making sense of the periods you go through thanks to transits. A well-read chart does not box you in: it shows you your levers.
To go further: how to read your birth chart, step by step.
Frequently asked questions
What is the difference between a birth chart, a natal chart and a chart wheel?
They are three names for the same thing: the representation of the positions of the planets, the zodiac and the houses at the moment and place of your birth. “Chart wheel” refers more to the drawing, “chart” more to its interpretation.
What is the difference between my sign and my birth chart?
Your sign (known as your Sun sign) is only the position of the Sun. The birth chart also includes the Moon, the Ascendant and eight other planets, each in a sign and a house, along with their aspects: it is an infinitely finer description.
Can a birth chart change?
No, the natal chart is fixed: it describes the moment of birth. What evolves are the transits (today's planets), which activate one part of the chart or another over the course of life.
Why is the time of birth so important?
Because the Ascendant changes sign roughly every two hours and the houses depend on it. Without a time, you know the planets in signs but not the areas of life where they act.