Accurate astronomical calculation
Find the sign that was rising when you were born.
The Ascendant changes quickly and cannot be found from a birthday alone. Use the time recorded at birth whenever possible.
What this calculator uses
The calculator converts your recorded local time using the historical IANA timezone for your birthplace—not today’s UTC offset. It then calculates the eastern-horizon intersection at those coordinates.
If your time is unknown, we will not guess a Rising sign. A birth certificate or contemporaneous record is usually the most useful source.
All positions use the tropical zodiac. When time is known, houses use the Placidus system. Calculations are deterministic; no AI is used to produce astronomical coordinates.