What tithi was it?

Any date from 1950 onward, in eighteen cities, computed at that city's own horizon.

Why the date is not enough

A shraddha is kept on the tithi of the death, not on its date in the Gregorian calendar. The two drift apart: a death on 12 March 2019 fell on Shukla Shashti, and Shukla Shashti will not land on 12 March again in a lifetime. To keep the day you need the tithi, and to find the tithi you need the panchangam for the date itself.

The same is true of a birth star. A child born on a given morning has a nakshatra, and that — not the calendar date — is what a horoscope, a naming and a marriage match are built on.

What you get

The tithi and paksha running at that city's sunrise, with the hour it gave way. The nakshatra, yoga and karana with their endings. Sunrise and sunset, moonrise and moonset. Rahu kalam, yamagandam and gulikai for that day.

Why the city matters

A tithi ends at one instant everywhere on earth, but which tithi is running at sunrise depends on when the sun rises where you are. Chennai and Delhi differ by about forty minutes, and on a day where a tithi turns inside that gap the two cities name the day differently. Pick the place the family keeps the observance.

How a tithi is computed · why the day starts at sunrise · the same data as JSON