Birth chart calculator
Calculate your Sun, Moon and planetary placements from your birth details. Add a known birth time and location for your rising sign and whole-sign houses. The chart includes Pluto and retrograde indicators; its interpretations follow astrological traditions.
How to calculate your natal chart
- Enter your birth date and the local clock time recorded at birth. If the time is unknown, select that option instead of guessing.
- Choose your birth city. The location determines the horizon used for the rising sign; the city list supplies a standard UTC offset.
- Check the UTC offset that applied on your birth date. Historical time-zone rules can differ from today. The daylight-saving box adds one hour, so do not add it again if your entered offset already includes that adjustment.
- Calculate the chart, then read each body's sign and degree. Houses appear only when a birth time is supplied.
For example, 14:00 at UTC+2 represents 12:00 UTC. Using UTC+1 for the same clock time represents 13:00 UTC, which can change the rising sign and houses. If your city is missing, a nearby city is only an approximation of your birthplace.
Why birth chart calculators disagree
Compare the input time and UTC offset first, then the zodiac and house system. This tool uses the tropical zodiac and whole-sign houses. A sidereal chart or a chart with Placidus houses can give different labels or house placements from the same birth details. With an unknown time, the noon result cannot settle a Moon sign close to a boundary.
Start with the Sun, Moon and rising sign, then explore individual placements. For a discussion of the chart's symbolic meaning, see our astrology reading guide. A reading is an interpretation, not a verified forecast of events.
Method reference: Paul Schlyter's planetary-position methods. For the astronomy behind apparent backward motion, see NASA's retrograde explanation. These sources explain astronomical calculations and motion; they do not validate astrological interpretations.
What each placement is for
SunIdentity
The self you build on purpose and recognise as you. This is the sign almost everyone already knows, and it is one placement out of a dozen.
MoonEmotional default
How you react before you have decided how to react, what settles you, and what you need to feel safe. Usually the placement people find most accurate.
Ascendant (rising sign)The arrival
How you come across before anyone knows you. It depends on your exact birth time, which is why a chart without one is missing its frame.
MercuryThinking and speech
How you take information in and how you hand it back. It never strays far from the Sun, so it is either your Sun sign or one adjacent to it.
VenusWhat you value
Taste, affection, and what you find worth having. In relationship readings it carries more weight than the Sun does.
MarsDrive and anger
How you pursue what you want and what you do when blocked. Two people with the same Sun and different Mars fight nothing alike.
JupiterGrowth and excess
Where you expand, take chances and overreach. It spends about a year in each sign, so it is shared with everyone born around the same time.
SaturnLimits and discipline
Where the work is, and where you are slowest to feel adequate. Its return at about twenty-nine is the transit people notice most.
UranusDisruption
Where you break the pattern. Seven years to a sign, so it describes a generation more than a person.
NeptuneImagination and blur
Where the edges go soft — inspiration, and also where you are easiest to fool. Around fourteen years to a sign.
PlutoPower and change
Where things are stripped down and rebuilt. It takes twelve to thirty years to cross a sign, so it marks an era.
Why two people born the same day are not alike
The Sun takes a month to cross a sign, so everyone born in the same few weeks shares it. The Moon crosses one in two and a half days, and the ascendant in about two hours. That is where the differences live: the same birthday at a different hour can produce different placements. Astrologers interpret those differences symbolically.
The slow planets work the other way. Uranus spends seven years in a sign, Neptune about fourteen, Pluto twelve to thirty — so those placements are often interpreted as generational themes in astrology. They do not establish an individual personality or predict a life outcome.
Frequently asked questions
What is a birth chart?
A birth chart, or natal chart, is a map of where the Sun, Moon and planets were at the moment and place you were born. Your sun sign is one line of it. The chart adds the Moon, the ascendant, the seven other bodies, and the houses those bodies fall in — which is why two people born on the same day can read nothing alike.
Do I need my exact birth time?
An exact time is needed for the ascendant and houses. If you select unknown birth time, this calculator uses noon in the selected local time zone and omits both. Planetary positions are then estimates for that time: the Moon, and any body near a sign boundary, may have a different sign at your actual birth time.
What does retrograde mean in a birth chart?
Retrograde means apparent backward motion against the background stars as seen from Earth, caused by the relative motion of the planets. The planet does not reverse its orbit. This calculator marks a body retrograde when its calculated longitude decreases over a short interval around the selected time.
Which house system does this use?
Whole sign: the rising sign forms the first house, the next sign the second, and so on. Results can differ from charts using Placidus or another house system. Whole-sign houses still depend on the correct rising sign; an uncertain birth time can change the entire house arrangement.
How accurate are the positions?
This is an approximate tropical-zodiac calculation for years 1800–2100. It uses orbital elements with selected perturbation corrections and a separate lunar calculation. Check the birth time, location and historical UTC offset before comparing results. Small differences between calculation methods matter most near a sign boundary; the displayed precision is not a guarantee of positional accuracy.
Is my birth data stored?
No. Everything is calculated in your browser. Your birth date, time and city are never sent to our servers, logged, or attached to an account.
Keep going
Moon sign calculator · Rising sign calculator · All twelve sign profiles · Chinese zodiac