Ayanamsa = precession correction, the difference between tropical (Western) and sidereal (Vedic) zodiac positions. Parashara-based systems typically use Lahiri ayanamsa (also called "Indian standard ayanamsa").
KP uses its own ayanamsa, slightly different from Lahiri. In 2024:
Lahiri ayanamsa ≈ 23°56'
KP ayanamsa ≈ 23°12'
Difference ≈ 44 minutes, which moves planets by less than 1 sign but can shift nakshatra boundaries. This matters for horary (prashna) charts, where precision is critical.
Historical reason: K. Krishnamurti calibrated his ayanamsa to match his own observation data and horary results, rather than adopting Lahiri wholesale. Some schools claim KP ayanamsa is more accurate for horary; others argue they are equivalent for natal charts but diverge in horary.
Practical implication: A client's horoscope computed in KP using KP ayanamsa will show planets in slightly different positions than if computed in Parashara using Lahiri. For most purposes, the difference is negligible; for horary (Prashna) and event timing, it can matter.
The calculator uses KP ayanamsa for all KP computations. When comparing KP results to Parashara (Lahiri ayanamsa) results, note that the ayanamsa difference is one source of divergence.
You will compute the same chart in both ayanamsas and observe the difference. For most placements, it is under 1°; for some nakshatras, it can cross a boundary.