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Zero Degree Alchemy

Birth Chart Calculator

Your natal chart, calculated from the exact minute you arrived, rising sign, houses, every placement and aspect. Free, and precise to the arcsecond.

On your birth certificate. Exact time changes your rising sign, houses, and Human Design profile, if you're unsure, the numbers below still hold.


Human Design
Natal Astrology
BodyPlacementHouse

Numerology

This is the surface

Your full reading connects these three systems, where your Human Design authority meets your chart ruler, where your personal year meets your transits. That's where it stops being data and starts being useful.

What a birth chart actually is

A birth chart, also called a natal chart, is a map of where every planet sat the moment you took your first breath, drawn from where you were standing. Not the day. The minute. The sky rotates a full degree every four minutes, so two people born the same morning in the same hospital can have different rising signs and, with them, a completely different chart shape.

The three things people miss

Your rising sign matters more than your Sun sign

The Ascendant is the exact degree of the zodiac climbing over the eastern horizon at your birth. It sets the entire house structure, which areas of life each planet governs for you. Sun-sign horoscopes ignore it entirely, which is why they so often read as vague.

Houses are the part that makes it personal

Two people can both have Venus in Scorpio. If one has it in the 7th house and the other in the 2nd, it means something different in each life: partnership versus resources. Houses come from your birth time and place. Without them, a chart is generic.

Retrogrades are a real position, not a mood

A planet is retrograde when it appears to move backward from Earth's vantage. This calculator marks each one with ℞ and gives its actual speed, so you can see how close to stationary it was, a planet barely moving at your birth carries far more weight than one at full speed.

What this calculator gives you

How accurate is it?

Positions come from the Swiss Ephemeris. The same astronomical library professional astrology software runs on. The engine behind this page is tested against a published birth chart with a birth-certificate-verified time, and agrees with independent published charts to under one arcminute. The calculation code is open source and its test suite runs on every deploy.

What you need

Date, time and place. If you don't know your birth time, a birth certificate usually has it; in many regions you can request one. Without a time you can still read your planets by sign, but the Ascendant and houses can't be calculated, those are the parts that make the chart yours.

Common questions

What is a birth chart?

A birth chart, also called a natal chart, is a map of where every planet sat at the exact moment you were born, drawn from the place you were born. It uses the minute, not just the day, because the sky rotates roughly one degree every four minutes.

Do I need my exact birth time for a birth chart?

For the full chart, yes. Your Ascendant (rising sign) and house placements are calculated from the birth time and place. Without a time you can still see which sign each planet was in, but not the houses or rising sign.

What is the difference between a birth chart and a natal chart?

They are the same thing. 'Birth chart' is the everyday term and 'natal chart' is the term astrologers more often use. Both describe the same calculation.

Is this birth chart calculator free?

Yes. The calculator is free and returns your full chart instantly, including houses, aspects and retrogrades.