This page is designed to teach the basic concepts of Sha'ot Zmaniot . Sha'ot Zmaniot is the system which governs the valid times of prayer for the Jewish day. Times are based on fractions of the number of daylight hours. The number of daylight hours is calculated by subtracting the time of sunset from the time of sunrise.
| Abbr. | Meaning | Formula |
|---|---|---|
| SZ"KSH | Sof Zman Kri'at Sh'ma - the latest time to say the Sh'ma | (sunset-sunrise)*0.25 + sunrise |
| SZ"TEF | Sof Zman Tefila - the latest time to pray the morning service (Shakharit) | (sunset-sunrise)/3 + sunrise |
| M.Ged | Minkha Gedolah - the earliest time to pray the afternoon service (Minkha) | (sunset-sunrise) * 13 / 24 + sunrise |
| M.Ket | Minkha Ketanah - the beginning of the first plag of the afternoon | (sunset-sunrise) * 19 / 24 + sunrise |
| Plg | Plag Minkha - the beginning of the second plag of the afternoon. The earliest time one can start the Sabbath | (sunset-sunrise) * 43 / 48 + sunrise |
| 40 + Shk | 40 minutes after sunset - one opinion on Tzet HaKochavim , the emergence of the stars, the ending of the Sabbath. | sunset + 40 |
| Yav | 50 minutes after sunset - the opinion observed at the Yavneh House of Princeton for Tzet HaKochavim , the emergence of the stars, the ending of the Sabbath. | sunset + 50 |
| R"T | Rabbeinu Tam - the most stringent opinion on Tzet HaKochavim , the emergence of the stars, the ending of the Sabbath. | sunset + 72 |
Now that you understand the basics, insert the times for sunrise and sunset (24hr. time, please). Example: 6:00 18:00 is the classic 6 to 6 day.
(You can check out the US Naval Observatory's Sunrise/Sunset Table for the correct times in your area.
This page was designed by Jonathan Novich ©Copyright, 1996