Zmanim are the times of day that govern practice: dawn, sunrise, the deadlines for the Shema and the Amidah, midday, the times for Mincha, sunset and nightfall. They follow the sun rather than the clock, so they change every day and from one place to another.

What is a seasonal hour (sha'a zmanit)?

The halachic day is divided into twelve equal parts, however long it happens to be: those twelfths are the seasonal hours. In summer a seasonal hour runs over sixty minutes, in winter it is shorter. That is why “the third hour of the day” never falls at the same clock time.

What is the latest time to say the morning Shema?

The Shema is said until the end of the third seasonal hour of the day. Two opinions give two deadlines: the Magen Avraham, who counts the day from dawn to nightfall, and the Vilna Gaon, who counts it from sunrise to sunset. The gap easily reaches half an hour; both times are shown side by side.

What is the difference between the Magen Avraham and the Vilna Gaon?

Both divide the day into twelve equal hours, but not the same day: the Magen Avraham runs it from dawn (72 minutes before sunrise) to nightfall, the Vilna Gaon from sunrise to sunset. The Magen Avraham's day is therefore longer, and his morning deadlines fall earlier.

From when may Mincha be said?

Mincha gedola opens the time for Mincha, half a seasonal hour after midday (chatzot). Mincha ketana, two and a half seasonal hours before nightfall, is the preferred time to say it.

What is the difference between shkia and tzeit hakochavim?

Shkia is sunset, tzeit hakochavim is nightfall, when three stars are out. Between the two lies bein hashmashot, an interval of doubtful status: that is why Shabbat begins before shkia and only ends at tzeit.

What are alot hashachar and misheyakir?

Alot hashachar is dawn, the first light in the sky: the halachic day begins there. Misheyakir comes next, when there is enough light to recognise a familiar face: it is the earliest time to put on tallit and tefillin.

What time are Shabbat candles lit?

Eighteen minutes before sunset in most communities, forty minutes in Jerusalem. Shabbat ends at nightfall, the time for havdalah. The times for your city are on the Shabbat times page.

How are these times calculated?

From the position of the sun at your coordinates, at sea level: dawn and nightfall from the sun's depression below the horizon (16.1° for alot, 11.5° for misheyakir, 8.5° for tzeit), the morning and afternoon deadlines in seasonal hours. The whole computation runs on your device, offline, and your location goes nowhere. For practice, follow your community's published times.

Zmanim explained: every halachic time of the day

Alot hashachar, misheyakir, sunrise, sof zman Shema and Tefillah, chatzot, mincha gedola and ketana, plag hamincha, shkia, tzeit hakochavim: what each of these times marks, how it is worked out, and where to find it for your city. For today's actual times, see the Shabbat times page.

The halachic day and seasonal hours

Zmanim follow the sun, not the clock. The halachic day is divided into twelve equal parts, the seasonal hours (sha'ot zmaniyot): long in summer, short in winter. "The third hour of the day" therefore never falls at the same clock time, and it differs from one city to the next.

Two schools divide that day differently. The Magen Avraham runs it from dawn to nightfall; the Vilna Gaon from sunrise to sunset. Where practice really tells them apart, sof zman Shema and sof zman Tefillah, both times are given side by side.

Dawn and sunrise

Alot hashachar: dawn, when the sun is 16.1° below the horizon. The halachic day begins here; it is also when the minor fasts begin.

Misheyakir: the sun 11.5° below the horizon, when there is enough light to recognise a familiar face. This is the earliest time for tallit and tefillin.

Netz hachama: sunrise. Saying the Amidah of Shacharit exactly then is the preferred practice (the vatikin minyan).

The morning deadlines

Sof zman Shema: the end of the third seasonal hour. After it one still reads the Shema, but no longer fulfils the obligation to read it in its time.

Sof zman Tefillah: the end of the fourth seasonal hour, the last time for the morning Amidah.

Each of these two deadlines is given according to the Magen Avraham (earlier) and according to the Vilna Gaon.

The afternoon

Chatzot: midday, exactly halfway between sunrise and sunset.

Mincha gedola: half a seasonal hour after chatzot, when the time for Mincha opens.

Mincha ketana: two and a half seasonal hours before the end of the day, the preferred time to daven Mincha.

Plag hamincha: an hour and a quarter (seasonal) before the end of the day. From then on one may, according to the opinion that allows it, say Maariv and accept Shabbat early.

Evening and night

Shkia: sunset, the end of the day.

Bein hashmashot: the interval between shkia and nightfall, of doubtful status. It is to clear it that Shabbat starts before shkia and only ends once night has fallen.

Tzeit hakochavim: nightfall, the sun 8.5° below the horizon. This is the time for Maariv, the end of Shabbat and festivals, and the end of fasts.

Chatzot halayla: midnight in the halachic sense, the time for Selichot and Tikkun Chatzot.

Shabbat and festivals

Shabbat is brought in 18 minutes before shkia in most communities, and 40 minutes in Jerusalem, where the local custom is wider. It ends at tzeit hakochavim, the time for havdalah.

The times for your own city are on the Shabbat times page, week by week and city by city, and the festival dates on the Jewish holiday calendar.

How we compute them

From the position of the sun at your coordinates, at sea level. The whole computation runs on your device: it works with no connection, and your location goes nowhere. For practice, follow your community's published times: local custom comes before an astronomical calculation.

Frequently asked questions about zmanim

What are zmanim?: Zmanim are the times of day that govern practice: dawn, sunrise, the deadlines for the Shema and the Amidah, midday, the times for Mincha, sunset and nightfall. They follow the sun rather than the clock, so they change every day and from one place to another.
What is a seasonal hour (sha'a zmanit)?: The halachic day is divided into twelve equal parts, however long it happens to be: those twelfths are the seasonal hours. In summer a seasonal hour runs over sixty minutes, in winter it is shorter. That is why “the third hour of the day” never falls at the same clock time.
What is the latest time to say the morning Shema?: The Shema is said until the end of the third seasonal hour of the day. Two opinions give two deadlines: the Magen Avraham, who counts the day from dawn to nightfall, and the Vilna Gaon, who counts it from sunrise to sunset. The gap easily reaches half an hour; both times are shown side by side.
What is the difference between the Magen Avraham and the Vilna Gaon?: Both divide the day into twelve equal hours, but not the same day: the Magen Avraham runs it from dawn (72 minutes before sunrise) to nightfall, the Vilna Gaon from sunrise to sunset. The Magen Avraham's day is therefore longer, and his morning deadlines fall earlier.
What is plag hamincha?: Plag hamincha is the midpoint of the last stretch of the afternoon, an hour and a quarter (seasonal) before the end of the day. From then on one may, according to the opinion that allows it, say Maariv and accept Shabbat early.
From when may Mincha be said?: Mincha gedola opens the time for Mincha, half a seasonal hour after midday (chatzot). Mincha ketana, two and a half seasonal hours before nightfall, is the preferred time to say it.
What is the difference between shkia and tzeit hakochavim?: Shkia is sunset, tzeit hakochavim is nightfall, when three stars are out. Between the two lies bein hashmashot, an interval of doubtful status: that is why Shabbat begins before shkia and only ends at tzeit.
What are alot hashachar and misheyakir?: Alot hashachar is dawn, the first light in the sky: the halachic day begins there. Misheyakir comes next, when there is enough light to recognise a familiar face: it is the earliest time to put on tallit and tefillin.
What time are Shabbat candles lit?: Eighteen minutes before sunset in most communities, forty minutes in Jerusalem. Shabbat ends at nightfall, the time for havdalah. The times for your city are on the Shabbat times page.
How are these times calculated?: From the position of the sun at your coordinates, at sea level: dawn and nightfall from the sun's depression below the horizon (16.1° for alot, 11.5° for misheyakir, 8.5° for tzeit), the morning and afternoon deadlines in seasonal hours. The whole computation runs on your device, offline, and your location goes nowhere. For practice, follow your community's published times.