FREE BIRTH-CHART TOOL
Free Big Three & Birth Chart Calculator
Use the birth details you have to see a careful, immediate Big Three result. No account, email, or payment is required.
For a known local birth time and selected birthplace, this calculator returns the Sun, Moon, rising sign, and a concise placement list. It is a starting point for reflection, not a diagnosis, prediction, or guarantee.
If your birth time is unknown, choose that option. The result intentionally withholds the rising sign, houses, and angles instead of guessing a noon chart.
No account required
Calculate your Big Three
Your result stays in this browser tab and is cleared when you reload.
Astrology is offered for reflection and entertainment, not professional advice or a guarantee about your future.
A private, immediate starting point
Enter the birth details you have. We calculate only what that information can support and do not create an account, report, or saved chart.
How this calculation handles your details
Birthplace search is an explicit action, not autocomplete. When available, the search request is sent from our server to OpenStreetMap Foundation's Nominatim service separately from your birth date and time. Results carry OpenStreetMap data; see the Nominatim usage policy.
The calculation uses Swiss Ephemeris data with the resolved IANA timezone and local daylight-saving rules. If a local time is duplicated or does not exist, the tool asks you to correct or specify it rather than silently choosing a result.
If you have an approximate centre time, the Birth-Time Uncertainty Explorer compares selected categories at a fixed set of nearby sampled times. It does not find or correct a birth time.
Read more about what a birth chart is, why birth time matters, zodiac signs, the twelve houses, or follow the birth-chart learning path.
Frequently asked questions
What are the Big Three?
In astrology, the Sun sign, Moon sign, and rising sign are commonly used as a first introduction to a birth chart. They are symbolic tools for reflection, not scientific measures of personality or future outcomes.
Why does birth time matter?
The rising sign and houses change with local time and birthplace. An exact time can therefore change the chart structure, while date-based placements may still be useful when time is unknown.
What happens if I do not know my birth time?
The calculator withholds rising sign, houses, angles, and house-based interpretations. It shows only placements that remain stable during the selected local date and marks a placement that may change.
Is my result saved?
No. This tool does not create an account or saved chart. Your result stays in browser memory and is cleared when you reload the page.