Natal Chart Online

What the natal chart calculator actually computes

A natal chart records the positions of the planets, angles and houses at the moment of birth. The calculator resolves each planet's longitude to the arcsecond and the house cusps to the arcminute, then builds the full aspect list with real orbs instead of rounding to whole degrees.

Everything is computed in your browser through Swiss Ephemeris compiled to WebAssembly. Your birth date, time and coordinates never leave the device unless you save the chart to your account. Once the page has loaded, the calculator keeps working even without a connection.

• •Planets from the Sun to Pluto, mean and true lunar nodes, Lilith, Chiron
• •All twelve house cusps, Ascendant, Midheaven, Vertex
• •Aspects with the exact orb and a marker showing whether they are applying or separating
• •Element, modality and hemisphere distribution across the chart

What data you need, and what to do without a birth time

A complete chart needs the date, time and place of birth. Time matters most for the Ascendant and the houses: four minutes shift the Ascendant by roughly one degree, and two hours can move it into the next sign, taking the whole house structure with it.

If the time is unknown, tick the corresponding box. The chart is then built for noon, houses and the Ascendant are hidden, and you keep the planetary positions by sign along with the aspects between them. Keep in mind that the Moon travels 12 to 15 degrees a day, so its sign in such a chart deserves a separate check.

• •Cities are looked up in the atlas, coordinates and time zone fill in automatically
• •Historical daylight saving shifts follow what the country actually did that year, not today's rule
• •Coordinates can be entered by hand when a location is missing from the atlas

How to read the result

A planet answers what, a sign answers how, a house answers where. The Sun in Libra in the seventh house and the Sun in Libra in the tenth read very differently: one is about partnership, the other about public standing, even though the sign is identical.

Aspects show how parts of the chart are wired together. Look past the aspect name and check the orb: a conjunction with a 12 arcminute orb works far more strongly than the same conjunction at seven degrees. The aspect table lists the orb for every pair, so the tight configurations stand out immediately.

• •A stellium, meaning three or more planets in one house, marks the theme the chart is organised around
• •A planet sitting on a cusp works for both houses, not only the one it formally occupies
• •Retrograde planets are marked with an R and read as turned inward, not as damaged

House systems and zodiac type

Placidus is the default because most Western schools use it. Above roughly 66 degrees of latitude it produces badly distorted houses, and Equal or Whole Sign, where each house equals one sign, serves better there.

The tropical zodiac is tied to the spring equinox, the sidereal one to the actual constellations. The gap between them is currently about 24 degrees, so most planets land in the previous sign in a sidereal chart. Pick the one your school works with and avoid mixing the two in a single reading.

• •Placidus, Koch, Regiomontanus, Campanus, Equal, Whole Sign and several more
• •Tropical and sidereal zodiac with a choice of ayanamsa, including Lahiri and Fagan-Bradley
• •Settings are stored in your account and applied to every chart you build afterwards

Why charts from different sites disagree

The most common source of disagreement is the time zone. Many calculators take today's daylight saving rule and apply it to past years, although Ukraine, Poland and the United States all changed those rules more than once. A one hour error gives a different Ascendant and sometimes a different Moon sign.

The second source is orbs and the aspect set. One site counts only major aspects within eight degrees, another adds the quincunx and the semi-square. The third is the choice between the true and the mean lunar node, which can differ by up to a degree and a half. All three parameters are visible in the settings here, so any chart can be reconciled with any other program.

What to do with the chart next

The natal chart is a starting point. From there you look at how the current sky interacts with it: transits show events and periods, progressions show inner maturation, and the solar return sets the theme of the year from one birthday to the next.

A chart saved to your account is passed to every other tool automatically, so birth data is entered once. Synastry picks it up to compare with a partner's chart, transits to calculate any date, astrocartography to draw the world map of planetary lines.

• •Transits for today or for any date in the past or future
• •Synastry and composite charts for relationship work
• •Directions, progressions, profections and firdaria for forecasting
• •Astrocartography if relocation is on the table