Rising sign calculator
Enter your birth date, time, and city. If you don't know the time, you will get an hour-by-hour table of the rising sign for your birthday instead.
How this calculator works
The ascendant is computed from the local sidereal time at your birth place and the obliquity of the ecliptic at that instant. Without a birth time, the calculator steps through your birth date every five minutes and refines each change to within a minute.
The rising sign also sets the houses. For houses, planets, and aspects, use the birth chart calculator.
Questions
- Can I find my rising sign without my birth time?
- Not as a single answer. The rising sign (ascendant) is the sign coming up over the eastern horizon, and all twelve signs rise in turn over about 24 hours. Without a time, this calculator lists the hours when each sign was rising at your birth place on your birth date. If you know roughly when you were born, such as early morning or late evening, that table narrows it to one or two signs.
- Why do some signs rise for much longer than others?
- The zodiac meets the horizon at an angle that changes through the day. In the Northern Hemisphere, Cancer through Sagittarius take longer to rise and Capricorn through Gemini rise quickly; in the Southern Hemisphere it is the reverse. The difference grows the farther the birth place is from the equator, which is why the table rows have uneven lengths.
- How accurate does my birth time need to be?
- The ascendant moves about one degree every four minutes on average. A time that is off by half an hour can change the rising sign when the birth falls near the edge of a row in the table, and rarely matters when it falls in the middle.
- Does the house system change my rising sign?
- No. The rising sign is the same in Placidus, whole-sign, and every other house system, because it is defined by the horizon rather than by how the houses are divided.
- Is my birth data saved anywhere?
- No. The sign is computed by JavaScript in your browser and nothing is sent to a server. The page link keeps your date and place so you can come back to the result, so share that link only with people you would tell your birthday to.
Reference, not advice
This is cultural and astronomical reference, not personal prediction or advice.
This calculator is a reference tool. Astrology is documented cultural and historical material; it is not a scientifically demonstrated method of prediction. See the disclaimer.
Last reviewed .