How is a natal chart calculated?

Enter birth date, time, and place. Aurapure converts local time to UTC via IANA timezone and calculates planets, Placidus or Whole Sign houses, Ascendant and MC with Moshier ephemeris.

Can I calculate without birth time?

Yes, with unknown birth time: we show planets at local noon but not exact Ascendant, houses, or aspects.

Moshier is accurate to about an arcminute, enough for interpretation. Golden tests compare planets with JPL Horizons and angles with astro.com swetest.

Does data stay on device?

Calculation runs on the server; parameters stay in the URL. Email is sent only with explicit consent. No tracking cookies unless analytics is configured.

Yes for calculation and the intro reading. The email report requires consent.

Natal chart

Calculate your natal chart with Moshier ephemeris: planets, Placidus or Whole Sign houses, Ascendant, MC, aspects, and SVG wheel.

Quick answer

Aurapure's natal chart calculates planets, Placidus or Whole Sign houses, Ascendant and MC using Moshier ephemeris and IANA timezones with historical DST. Enter birth date, time, and place: basic calculation and intro reading are free; full report requires email and consent.

Enter birth date, time, and place to generate your natal chart.

Explore astrology

How to calculate a natal chart

1Enter date, time, and place. Provide birth day, month, and year, time (or select unknown time), and birthplace.
2Choose the house system. Placidus is the default; at polar latitudes Aurapure automatically falls back to Whole Sign.
3Run the calculation. The engine converts local time to UTC via IANA zones and computes planets, houses, Ascendant, and MC with Moshier ephemeris.
4Read the result. The wheel shows positions and aspects; the intro reading describes the chart's main themes — symbol, not forecast.

What is a natal chart?

A natal chart maps the sky at the exact moment and place of birth: planet positions, signs, houses, and aspects between celestial bodies. In symbolic astrology it is a portrait of the context you were born into — not a predictive horoscope.

How do you read it?

Start with the big three: Sun (identity), Moon (affective climate), Ascendant (how you show up). Then look at planets by sign and house, and aspects (conjunctions, trines, squares…) that link themes together.

Why does birth time matter?

Without an exact time you cannot compute Ascendant, houses, or angular aspects. With unknown time we show planets at local noon: useful for a first look, but incomplete.

What is this tool for?

To explore your chart with verifiable calculations and sober readings. Aurapure does not promise destinies: it offers symbolic coordinates to compare with your own experience.

Hand-coloured plate from 1660: the Earth at the centre, ringed by the band of the zodiac with its twelve signs, astronomers and angels at the edges — The zodiac in Cellarius's atlas
Andreas Cellarius, Harmonia Macrocosmica (Amsterdam, 1660), plate II: the band of the zodiac around the Earth in the Ptolemaic system.
Public domain, Wikimedia Commons

Frequently asked questions

How is a natal chart calculated?: Enter birth date, time, and place. Aurapure converts local time to UTC via IANA timezone and calculates planets, Placidus or Whole Sign houses, Ascendant and MC with Moshier ephemeris.
Can I calculate without birth time?: Yes, with unknown birth time: we show planets at local noon but not exact Ascendant, houses, or aspects.
Placidus or Whole Sign?: Placidus is the default. At polar latitudes (|lat| > 66°) we automatically fall back to Whole Sign because Placidus is undefined.
How precise is it?: Moshier is accurate to about an arcminute, enough for interpretation. Golden tests compare planets with JPL Horizons and angles with astro.com swetest.
Does data stay on device?: Calculation runs on the server; parameters stay in the URL. Email is sent only with explicit consent. No tracking cookies unless analytics is configured.
Is it free?: Yes for calculation and the intro reading. The email report requires consent.