Free Birth Chart
With your birth date, time and place we draw your full zodiac wheel: planets, houses and aspects, calculated from real ephemeris data, not rounded tables.
What a birth chart is
A birth chart, or natal chart, is a map of the sky at the exact moment and place you were born: where each planet sat, which sign was rising over the horizon, and how those points related to one another. It is a symbolic system with centuries of tradition behind it, not a scientific measurement or a prediction.
This calculator gives you the raw data: positions, houses and aspects. From there, different astrological traditions interpret them differently, and that interpretation is the part that turns numbers into meaning.
How to read the wheel
The outer ring of the wheel shows the twelve zodiac signs, always in the same order starting from Aries. The inner ring, split into twelve numbered sectors, shows the houses: each one governs an area of life, from house 1 (identity) to house 12 (the hidden). The symbols placed around the wheel are the ten planets, positioned in the sign and house they occupied at birth.
The lines crossing the centre of the wheel are the aspects: the angles the planets form with each other. Red lines mark tense aspects, such as the square or the opposition; blue lines mark harmonious ones, such as the trine or the sextile. The more lines converge on a planet, the more symbolic weight it usually carries in a reading.
We don't require an exact angle to draw an aspect: a margin, called the orb, is allowed. We use 8 degrees for the conjunction and the opposition, 7 for the trine and the square, and 5 for the sextile, widened to 7 when the Sun or the Moon is involved, since they move faster and get a bit more leeway.
| Aspect | Orb |
|---|---|
| Conjunction (0°) | 8° |
| Opposition (180°) | 8° |
| Trine (120°) | 7° |
| Square (90°) | 7° |
| Sextile (60°) | 5° (7° with Sun or Moon) |
Why it's free, and what the written reading adds
Calculating your birth chart costs nothing because it is positional maths: a date, time, place and a well-built ephemeris are enough to place every planet. What this calculator cannot give you is a connected interpretation: what your Venus in house 7 means combined with your Saturn in Capricorn, for instance.
The paid reading is text generated by AI from your exact positions: it interprets your chart by areas of life, such as personality, relationships and work, and links the data together, instead of giving you loose planet-by-planet definitions.
What you need
Your birth date, time and city. With the city we fix exact coordinates through OpenStreetMap and work out the historical time zone for that day, including daylight saving if it applied. Without a birth time we can still calculate the planets, but not the rising sign or the twelve houses: those stay blank on the wheel.
Frequently asked questions
Do I need my exact birth time?
For the ten planets it is not essential, though it helps pin down the Moon precisely. For the rising sign and the twelve houses it is required: without it, that part of the wheel cannot be calculated reliably and is left blank.
Which house system do you use?
The Placidus system, the most widely used in modern Western astrology. It divides the sky by the time each point takes to cross the horizon, not into equal parts, so the twelve houses are usually not the same size.
Where do the planet positions come from?
From the Moshier ephemeris, an astronomical calculation library checked against Jean Meeus's classic formulas. These are the same positions used by astronomy software, applied here to the tropical zodiac, the one based on the seasons.
Do you store my birth data?
We use it for the calculation and, if you request the paid reading, to generate it and save it to your account. We do not share it with third parties or use it for anything beyond your birth chart.
Why doesn't the free wheel include interpretation?
Because interpreting a whole chart, cross-referencing planets, houses and aspects with each other, is a writing task, not just a calculation. That is what the paid reading does: text generated by AI from your exact positions.