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Your birth chart, to the minute.

Free, exact, computed in your browser.

My name is , and I was born on
Birth date
mmddyyyy
 at
Birth time
hhmm
AM or PM
in .

Customise the wheel

Every tradition draws the sky a little differently. Tune the frame; the astronomy stays exact.

The chart changes what is computed

Zodiac

Tropical follows the seasons; sidereal follows the fixed stars.

House system

How the local sky is cut into twelve houses. Needs a birth time.

Lunar points

Mean smooths the Moon's wobble; true follows it exactly.

Nodes
Lilith

Aspect orbs

How wide a miss still counts as a contact. Tighter finds fewer, sharper aspects.

Orbs are calibrated per pair: the Sun and Moon reach wider, Chiron, the nodes, and asteroids tighter, angles tighter still. The profile scales all of them together.

Extended sky

Historical time

Early records may use local mean time or a civil offset the modern time-zone database doesn't know. A researched offset entered here overrides the zone without moving the birthplace.

Leave blank for automatic historical conversion.

The wheel changes only the drawing; every table keeps the full chart

Bodies drawn

14 of 14

Luminaries

Personal

Social and outer

Points

Aspect lines

4 of 4

Which chords the wheel draws, with each type's orb under the selected profile.

Conjunctions never draw a chord: those bodies already stand together on the rim.

Degrees on the wheel

Without a birth time the wheel prints whole degrees only: the range a body swept that day, which is all the missing hour allows.

Sign lettering

Line treatment

Faded weighs each chord by its orb; vivid draws every chord at full strength.

Fair questions, straight answers.

Is this birth chart calculator really free?
Yes, the whole chart: planets, houses, angles, aspects, patterns, computed in your browser with no account and no email wall. The Deep Reading is the paid part, and it is optional. The free chart is the product, not the bait.
What if I don’t know my birth time?
Then we won’t pretend you do. Flip the switch and every fast-moving body shows its honest range across your birth day, aspects say whether they held all day, and no Rising sign gets invented out of thin air. Plenty of calculators quietly assume noon. We’d rather be right.
How accurate are the positions?
Ephemeris-grade. Planetary longitudes come from modern astronomical models, regression-tested against a Swiss Ephemeris matrix spanning 1800–2099, plus real equinox, solstice, eclipse, station, ingress, and house-cusp anchors. When something can’t be computed, the page says so instead of drawing it.
Which house systems are supported?
Placidus (the default), whole-sign, and equal, all in Customise. Near polar latitudes, where Placidus is mathematically undefined, the calculator tells you and falls back to whole-sign rather than faking cusps.
Tropical or sidereal?
Both. Tropical is the default; sidereal charts can use Lahiri, Fagan/Bradley, Krishnamurti, Raman, or Yukteshwar. Whichever you pick in Customise is applied consistently to bodies, angles, and house cusps, not just the Sun sign.
Can I calculate a historical birth chart?
Yes, from 1800 onward. The calculator uses historical time-zone data, and for records older than standard time you can enter a researched fixed UTC offset in Customise. It overrides the zone without moving the birthplace.
Is my birth data stored or sent anywhere?
The chart is computed on your device; nothing is uploaded to make it. As you type a birthplace, only those typed letters go to our own server to suggest towns; the lookup is never tied to you, though the typed text and its results may sit in an anonymous edge cache for up to a day so repeat lookups answer instantly. Your full birth data leaves the browser only if you buy the Deep Reading, and then only to generate it. A shared chart link carries the birth data inside the link itself, so pass it on as you would the data. Names never enter links at all.