The Challenge of Bikram Sambat Lunar-Solar Chronometry
Unlike the Gregorian calendar, where leap years follow rigid leap cycle rules, the Nepali Bikram Sambat (BS) calendar is a lunisolar system. Month lengths vary between 29, 30, 31, and 32 days depending on the Sun's precise astrological transit (Sankranti) through the 12 zodiac signs as calculated by the Nepal National Calendar Determination Committee (Nepal Panchanga Nirnayak Samiti).
131-Year Bit-Packed Kernel
To eliminate large external JSON files or network lookups, our engine bit-packs 131 years of historical and projected calendar data (from 1970 BS to 2100 BS) into compact hexadecimal strings. Each year's 12-month sequence requires only 6 bytes, allowing the entire 131-year ephemeris table to load in less than 3 kilobytes of memory.
Kathmandu Meridian Vedic Panchanga
Lunar Tithis, Nakshatras, and solar events are determined via high-precision solar longitude algorithms calibrated specifically for the Kathmandu meridian (85°19' E longitude, 27°42' N latitude), ensuring sub-second accuracy across all 77 districts of Nepal.