The Hijri calendar is purely lunar. Every month begins with a new crescent and lasts 29 or 30 days, because the Moon needs about 29.53 days to go through all its phases. Twelve such months make a year of 354 or 355 days.
What is the new moon?
At the new moon (conjunction) the Moon stands between the Earth and the Sun. Its lit side faces away from us, so it cannot be seen at all. Astronomers can calculate this moment to the minute, years in advance.
The hilal: the first crescent
A day or so after the new moon, a thin crescent appears low in the western sky just after sunset. This is the hilal. Whether it can be seen depends on the Moon’s age, its height above the horizon, the weather and where you are on Earth.
Calculation or sighting?
Saudi Arabia’s Umm al-Qura calendar is calculated in advance, so dates are known years ahead. Many communities still wait for the crescent to be seen with their own eyes. That is why the start of Ramadan or the Eids can differ by a day between countries.
Why Ramadan moves every year
The lunar year is about 11 days shorter than the solar year. Ramadan therefore comes about 11 days earlier each year and moves through every season in roughly 33 years — sometimes in long summer days, sometimes in short winter ones.
How we calculate the Moon here
The phase, the illuminated part and the distance are computed from the positions of the Sun and the Moon with standard astronomical formulas. New and full moon times are accurate to a few minutes; the picture shows the Moon as seen from the northern hemisphere.
The phases of the Moon
New moon
Waxing crescent
First quarter
Waxing gibbous
Full moon
Waning gibbous
Last quarter
Waning crescent
Frequently asked questions
What is the Moon phase today?
Moon phase today: New moon. 0% of its visible side is lit and the Moon is 29.0 days old. The next new moon is on Monday, 9 November 2026, the next full moon on Tuesday, 24 November 2026.
Is the Moon phase the same everywhere in the world?
Yes. The phase and the illuminated percentage depend only on the positions of the Sun, the Earth and the Moon, so at the same moment they are the same for everyone. What changes with your location is how the lit side is turned: in the southern hemisphere the picture is mirrored, near the equator the crescent lies almost flat.
What is the difference between the new moon and the hilal?
The new moon (conjunction) is the moment the Moon passes between the Earth and the Sun and cannot be seen at all. The hilal is the first thin crescent that becomes visible after sunset, usually 15 to 30 hours later. Islamic months begin with the hilal, not with the astronomical new moon.
Why does Ramadan start on different days in different countries?
Some countries follow a calculated calendar such as Umm al-Qura, others wait until the crescent is actually seen in their own sky. Because the crescent can be visible in one region and not yet in another, the first day of Ramadan or Eid can differ by one day.