Islamic holidays, also known as Muslim holidays or festivals, are based on the Islamic calendar, which is lunar and approximately 11 days shorter than the Gregorian calendar used globally. The exact dates of Islamic holidays can vary each year. In 2025, the Islamic calendar will be in the year 1446 AH (After Hijra). Here are some of the key Islamic holidays for 2025:

1. Eid al-Fitr (Festival of the Breaking of the Fast): This is one of the most important Islamic holidays and marks the end of Ramadan, the holy month of fasting. In 2025, Eid al-Fitr is expected to be observed around May 10th or 11th, depending on the sighting of the new moon.

2. Eid al-Adha (Festival of the Sacrifice): This holiday commemorates the willingness of Ibrahim (Abraham) to sacrifice his son Ismail (Ishmael) as an act of obedience to God, and it symbolizes the willingness to submit to God's will. In 2025, Eid al-Adha is expected to be celebrated around July 20th or 21st.

3. Al Isra' and Mi'raj (Night Journey and Ascension): This holiday celebrates the night that the Prophet Muhammad (peace be upon him) is believed to have traveled from Mecca to Jerusalem and then ascended to heaven. It is observed on the 27th of the month of Rajab, which, in 2025, will be around March 29th.

4. Ramadan (Month of Fasting): Ramadan is a holy month during which Muslims fast from sunrise to sunset. The month begins with the sighting of the crescent moon and ends with the sighting of the new moon that marks the beginning of Shawwal. In 2025, Ramadan is expected to start around April 2nd and end around May 2nd.

Please note that the exact dates of these holidays can vary based on the sighting of the moon, which is necessary to determine the start of a new month in the lunar calendar. Observances may also vary by region, as some countries may have different methods of moon sighting or may observe the holidays according to local customs. It is always a good idea to check the local calendar or consult with local religious authorities for the most accurate holiday dates.