What a natal chart shows
A birth chart, also called a natal chart, is a map of the sky drawn for one moment and one place on Earth. It records where the Sun, the Moon and the planets stood in the zodiac when you were born, plus a few calculated points.
Astrologers read the chart as a whole. A single placement is like one word, while the full wheel is the sentence that gives each word its context.
How to read the wheel, step by step
Start at the left side of the circle, at the horizontal line marked ASC. That is your Ascendant, the sign rising on the eastern horizon at your birth. The houses are numbered counterclockwise from there, so the first house sits just below the Ascendant.
Next, find the vertical line marked MC at the top. The Midheaven marks the highest point of the zodiac in your sky. The outer ring holds the twelve signs, and the planet glyphs sit inside it at their exact degrees.
Then look at which house each planet falls in. Finally, read the colored lines across the middle: these connect planets that form aspects. The table under the wheel lists every aspect with its exact orb, so you do not have to measure angles by eye.
Houses and aspects in plain words
Signs describe how a planet expresses itself, while houses describe where in life that energy is traditionally said to show up. The first house is linked with self and appearance, the fourth with home, the seventh with partners and the tenth with public life, for example.
Aspects are specific angles between two points. A conjunction (0 degrees) blends them, a trine (120) and a sextile (60) are read as easy flows, and a square (90) or an opposition (180) as tension that asks for effort. Placidus, Whole Sign and Equal are different ways of cutting the sky into houses, and many astrologers compare more than one.
Why the exact birth time changes everything
The planets move slowly enough that a few minutes rarely change their signs. The Ascendant is different. Because Earth turns once a day, the rising degree moves about one degree every four minutes and passes through a whole sign in roughly two hours on average.
Every house cusp depends on that rising degree. A birth time that is off by half an hour can move the Ascendant several degrees and shift planets into neighboring houses, so a time from a birth certificate or hospital record is worth finding.
No birth time? Here is what you still get
If you leave the time blank, we draw a noon chart. The planets are placed where they stood at midday, which keeps the error for the fast-moving Moon as small as possible. Houses, the Ascendant and the Midheaven are not shown, because they cannot be calculated without a time.
Even a noon chart shows sign placements and most aspects. From here you can isolate key parts with the Big Three calculator, see which houses hold what on the house calculator, or compare two people with a synastry chart. Our method page explains the math.