Natal chart from your date and place of birth
Online tool for calculating a natal chart — a birth horoscope — from a date, time and city. It computes the ten planets, Chiron, the lunar nodes and four asteroids, builds eleven house systems, an aspect grid, the full dignity table, the declinations and the conjunctions to fixed stars. The astronomy is checked against NASA JPL Horizons ephemerides: the largest disagreement is 8.6 arcseconds.
How to build a chart
Day, month and year. The calculation covers 1900 to 2099.
State the tolerance separately: to the minute, ±5 minutes or ±half an hour. If there is no time at all, tick "time unknown".
Start typing the city. Former names work too: type "Sverdlovsk" and the tool offers Yekaterinburg with the years the old name applied.
You get the wheel, tables of positions, houses and aspects, the time-zone breakdown, and a verdict on how firmly each placement is established.
Build a chart with an exact ascendant, houses and aspects
Calculation settings
How to read this chart
What every word on this page means. For each idea we say separately what was computed (that is checkable) and what tradition adds to it (that is not).
Sun sign
What people usually call "my star sign". It follows from the date alone — no time or place needed.
What is computed The Sun's ecliptic longitude at birth. The circle is cut into twelve 30° sectors; the sign is the sector number.
What tradition adds What that sector says about character. No checkable link has been found.
Moon sign
The Moon crosses the whole circle in 27 days and changes sign roughly every 2.5 days, so the hour of birth already matters here.
What is computed The Moon's longitude. It moves about 13° a day — half a degree an hour.
What tradition adds A link with emotional reactions and the need for safety.
Ascendant
The degree that was rising over the eastern horizon at the minute of birth. It changes faster than anything else — a full circle in a day.
What is computed Where the ecliptic meets the horizon in the east. We check it independently: the computed point must lie ON the horizon, and it does, within 7 arcseconds.
What tradition adds First impression, the way one enters a room.
Houses
Twelve sectors of sky around you: overhead, underfoot, to the east. Unlike signs they depend on the place and the minute.
What is computed Sector boundaries per the chosen system. Systems divide the sky differently, so a planet's house number can differ between them. That is not an error, just different divisions.
What tradition adds Each house is assigned an area of life: money, home, work, partnership.
Cusp
Simply a house boundary. "Cusp of the 7th" = where the seventh sector starts.
What is computed The boundary longitude in degrees.
What tradition adds A planet right on a boundary is said to work "in both houses".
Aspect and orb
An aspect is when the angle between two planets is close to a special value: 0°, 60°, 90°, 120° or 180°. The orb is how far from exact it may stray.
What is computed The angle between longitudes, to hundredths of a degree. We always print the orb used: without it two charts cannot be compared, and differing orbs are exactly why sites show different aspect counts.
What tradition adds That "hard" angles (90°, 180°) are difficult and "soft" ones (120°, 60°) come easily.
Retrograde (R)
A planet appears from Earth to move backwards. It is an optical effect: we overtake it, as an overtaken train seems to roll back.
What is computed The sign of the daily change in longitude. Negative means retrograde. Nothing moves backwards in space.
What tradition adds A turn inward, toward review rather than outward action.
Elements and modalities
The twelve signs split into four elements and three modalities. The percentages show what the chart has most of.
What is computed A weighted count: Sun, Moon and Ascendant weigh more than distant planets. A flat headcount would give different numbers, which is why the weights are shown.
What tradition adds That a dominant element describes a person's make-up.
Stable / borderline / undetermined
Our mark for whether a placement survives your time uncertainty. "Borderline" means: shift the time by the tolerance you gave and the sign or house changes.
What is computed The chart is built three times: at the stated time and at both edges of the tolerance. The mark is the comparison.
What tradition adds Nothing. This is our check, not an astrological notion.
Honestly, about what here is science
The astronomical half is exact science: positions are computed with VSOP87 and NOVAS and checked against NASA JPL Horizons ephemerides, with no disagreement beyond 8.6 arcseconds. Interpreting those positions is not science: controlled studies — Carlson's double-blind test in Nature (1985) and Dean and Kelly's work on people born minutes apart (2003) — found no effect. We compute the astronomy precisely and do not pass the interpretation off as established knowledge.
Chart balance
House systems compared
Why your chart differs from another site
I know my rising sign but not my birth time
If the birth time is unknown but you have been told your rising sign, we will show which hours of that day it was exactly that.
