Understanding this calculator
What this tool calculates
This calculator examines the lunar-month and year-name context for a specified date and observer. It distinguishes Amanta, in which months are delimited by new moons, from Purnimanta, in which month labels follow full-moon boundaries. The result also presents the relevant Samvatsara context under the selected Chaitra-year convention. These are defined calendar computations, not a universal claim that every region uses identical month and year naming. The engine follows calculated lunations and exposes leap-month treatment rather than assigning month names from a static Gregorian conversion table.
How to interpret the result
Start with the displayed Tithi, Paksha and both lunar-month names. In the Shukla half of a lunar month the two naming systems often agree, while in the Krishna half they can differ. The app's regression suite confirms this property rather than assuming one month label is always correct. A concrete fixture is September 2026 in Hyderabad, where a tested instant resolves to Amanta Shravana and Purnimanta Bhadrapada. The fixture illustrates a naming-convention difference, not two conflicting Moon positions. The engine also includes a test for the independently documented 2026 Adhika Jyeshtha lunation and checks its leap-month classification. When comparing calendars, ask whether a month is Adhika, what the lunation boundaries are, and which convention the publication follows. For Samvatsara, inspect the disclosed Chaitra new-year boundary instead of resetting the 60-year name list on January 1. The regression compares names around that astronomical boundary, including Vishvavasu and Parabhava. The tool can describe year-cycle names but cannot automatically know a family's regional Kartikadi or Vikrama-era practice without the appropriate rule. Use the intermediate lunar context to decide whether two apparently conflicting labels are actually based on different conventions.
Scope and limitations
The chosen calendar model does not claim to encode every local Almanac, Kshaya-month naming case, regional Vikrama calendar or ritual prescription. A Gregorian civil date may straddle a lunar or Samvatsara boundary, so changing the reference time or timezone can change the context. Leap-month names must not be guessed from the familiar twelve-month cycle. Religious observance dates should be checked with region-appropriate Panchanga rules beyond this explanatory month/year calculation. No predictive claim about the year follows from a Samvatsara label.