Fajr starts with the dawn or morning twilight. The time shown is the earliest Fajr time, when the faint twilight of dawn starts to become visible. This is known as Subha Sadiq – True Dawn. Fajr time ends just before Sunrise. Hanafi jurists usually set Fajr time (of Jamaat) about half an hour before sunrise, while Shafi jurists use the earliest time.
Zawal is when the sun is at its mid-point in the sky. Zuhr begins after mid-day when the sun has passed the mid-point (i.e. after Zawal). Generally, 5 minutes are added to Zawal time to get the earliest Zuhr time. Zuhr ends at the start of Asr time.
This is the earliest Asr time according to the Shafi school of jurisprudence. Asr begins when the
length of the shadow of an object exceeds the length of the object. The minimum length of shadow (at mid-day) is subtracted from the length of the shadow before comparing it with the length of the object.
This is the earliest Asr time according to the Hanafi school of jurisprudence. Asr begins when the length of the shadow exceeds TWICE the length of the object. The minimum length of shadow (at mid-day) is subtracted from the length of the shadow before comparing it with the length of the object.
Maghrib begins when the sun has completely set (Sunset complete). For safety, 3 minutes are added to the Sunset time, to derive the Maghrib time. It is strongly recommended to always add these 3 minutes, because prayer times vary slightly (+/- 1 minute or so), year to year, based on a four year cycle culminating in a Leap Year. Perpetual Time Tables cannot take these slight variations into account. Differences in Altitude also affect the Sunset time slightly, so the 3 minutes should always be added for safety, when computing the Maghrib time. The Maghrib time shown in the time table has 3 minutes added to the Sunset time, so the Maghrib Azaan may be called exactly at the time shown in the time table. This is also the Iftaar time.
Maghrib ends just before the start of Isha.
Isha starts after dusk when the evening twilight completely disappears. It has been established that the evening twilight completely disappears when the sun has set 18 degrees below the Horizon. This is called Astronomical Sunset. In a city area, it is difficult to see the faint evening twilight unless all the lights in the city are switched off. Isha is valid only after the evening twilight has completely disappeared. The Time Table shows the earliest Isha time for a locality. The Azaan for Isha Salah should not be called before this time.
Sehri time ends with the commencement of Fajr time. A fast will not be valid if one has to eat something after the start of Fajr time (Subha Sadiq – True Dawn). The Sehri time shown in the Time Table is calculated as 5 minutes before Subha Sadiq (earliest Fajr), for safety. This time should be regarded as final (Sehri Ends).