In Jaimini astrology the Atmakaraka is the planet at the highest degree in your chart: the soul significator, whose themes matter most for this lifetime. The planet at the lowest degree is the Darakaraka, read for the spouse. The Atmakaraka's sign in the Navamsa is the Karakamsha; the Upapada and Arudha Lagna are further Jaimini points for marriage and public image.

Every tool uses the same chart and the same classical rules as your full Kundli report, so the results always agree with your reading.