How the times are worked out
Every pachkhan time starts from the sunrise of the day and the city you choose, so the same vow has a different clock time in Ahmedabad, in Mumbai and in London, and a slightly different one tomorrow. The tool finds the sunrise and sunset for the place, measures the daylight between them, and then applies the divisions below. The same working builds the pages on our pachkhan times by city, so a city page and this tool agree to the minute.
- Navkarsi is 48 minutes after sunrise, one muhurta. It is the earliest time food or water is taken after the night’s vow.
- Porsi is one prahar after sunrise. A prahar is a quarter of the daylight, from sunrise to sunset.
- Sadh Porsi is one and a half prahars after sunrise.
- Purimaddh is two prahars after sunrise, when half the daylight has passed.
- Avaddh is three prahars after sunrise.
- Chauvihar is sunset. After it, a person keeping the chauvihar or tivihar vow takes no food until the next Navkarsi, and with chauvihar, no water either.
Because a prahar is a quarter of the actual daylight, it is about three hours in midsummer in Gujarat and shorter in winter. In London in June it is close to four hours; in December it is barely two. That is why a printed card from one city or one season does not carry over.
What the sunrise means here
Sunrise is the moment the upper edge of the Sun appears over a flat horizon, with the usual allowance for the air bending its light. This is the convention most printed panchangs use. It is a little earlier than the time at which the whole disc is clear, and it ignores hills and buildings. The Sun’s position is calculated from astronomical formulae and has been checked against the Swiss Ephemeris for thirty cities, with sunrise and sunset within about ten seconds.
The clock time shown is the local time of the city you chose, with daylight saving in force on that date. If you are in New Jersey and choose Ahmedabad, you see Ahmedabad’s clock, which is what a relative there is following.
Rounding, and why it is on the safe side
A time that ends a pachkhan is rounded up to the next minute, so it is never early for a vow. Sunset, which is a deadline, is rounded down. Some sanghs round to the nearest five minutes or add a margin of their own.
The tithi shown beside the times
Each day also shows the tithi (lunar day) current at sunrise, the moment it ends, and whether it is a parva tithi such as Bij, Pancham, Aatham, Agiyaras, Chaudas, Punam or Amas. For a fuller view of the parva days, with the kalyanakas that fall on a tithi, use the Jain tithi and parva day tool.
Your sangh comes first
These times are an aid, not a ruling. Upashrays and gacchas round the times differently, and Shvetambara, Sthanakvasi, Terapanth and Digambara practice can differ on small points. If your upashray or derasar publishes its own times, follow them. The vow is kept with your sangh, not with a website. Near the poles, where the Sun may not rise or set for weeks, the day cannot be divided into prahars at all; the tool says so rather than guessing.
For a single city with the next two weeks laid out, see the pachkhan times by city. For choghadiya, hora and the full panchang of any place, use the Jain Panchang. The wider practice is described on the samayik and pratikraman pages.
Frequently asked questions
↳ What is the difference between Navkarsi and Porsi?
Navkarsi is the shortest pachkhan and ends 48 minutes after sunrise. Porsi is longer: it ends one prahar, a quarter of the day's daylight, after sunrise. Which one a person takes is a matter of their own vow and their sangh's practice.
↳ Why do the times change every day?
Because they are measured from the day's own sunrise and the length of that day's daylight, and both change slowly through the year. The change is small from one day to the next, but over a season it adds up to an hour or more in some cities.
↳ Which time do I use for Chauvihar?
Sunset. The tool shows sunset in your city, rounded down so that it is never late. Many families make a habit of finishing the evening meal a little before it.
↳ Why does my temple's card show different times?
Usually because the card is printed for one city or for a rounded date, or because the sangh rounds to five minutes or adds a margin. Use your sangh's times if it publishes them.
↳ Does it work outside India?
Yes. Choose any city in the world; sunrise, sunset and the local time zone, with daylight saving, are worked out for that place and date.