Settings

Choose Tropical for Western-style charts, a sidereal ayanamsha for Vedic-style charts, or add your own

Used as the chart's viewing location - affects the ascendant, houses, and rise/set based calculations

North Indian and South Indian both use whole-sign houses (each house = one full sign). Circular shows real house sizes based on your House System setting below - useful for seeing Placidus/Sripati's unequal houses, which a fixed grid can't represent.

Applies everywhere in the app - unlike Chart Style/Nodes, this isn't a per-chart setting.

How house/bhava cusps are calculated. Whole Sign is the traditional Vedic default; Sripati is the traditional Vedic unequal-house system

Western aspects (conjunction, sextile, square, trine, opposition) are mutual and use the average of both planets' orbs. Vedic special aspects are one-directional and use only the aspecting planet's own orb. House cusps have no orb of their own either way - they're only ever a target, never an aspecting point.

Bhachakra's calculation server is open source under the GNU AGPL. Planetary positions come from the Swiss Ephemeris by Astrodienst.