Eid al-Fitr (Arabic: عيد الفطر, romanized: ʿĪd al-Fiṭr, lit. 'Festival of Breaking the Fast') is the first of the two main festivals in Islam, the other being Eid al-Adha. It falls on the first day of Shawwal, the tenth month of the Islamic calendar. Eid al-Fitr is celebrated by Muslims worldwide as it marks the end of the month-long, dawn-to-dusk fasting (sawm) during Ramadan. The holiday is known under various other names in different languages and countries around the world.

Eid al-Fitr has a particular salah that consists of two rakats generally performed in an open field or large hall. It may only be performed in congregation (jamāʿat) and features six additional Takbirs (raising of the hands to the ears whilst reciting the Takbir, saying "Allāhu ʾAkbar", meaning "God is the greatest"). In the Hanafi school of Sunni Islam, there are three Takbirs at the start of the first rakat and three just before rukūʿ in the second rakat. Other Sunni schools usually have 12 Takbirs, similarly split in groups of seven and five. In Shia Islam, the salat has six Takbirs in the first rakat at the end of Tilawa, before rukūʿ, and five in the second. Depending on the juristic opinion of the locality, this salat is either farḍ (فرض, obligatory) or mustaḥabb (strongly recommended). After the salat, Muslims celebrate the Eid al-Fitr in various ways with food being a central theme, which also gives the holiday the nickname "Sweet Eid" or "Sugar Feast".

According to Muslim tradition, Muhammad instituted the celebration of Eid al-Fitr. According to a certain hadith, these festivals were initiated in Medina after the migration of Muhammad from Mecca. Anas ibn Malik, a companion of Muhammad, narrated that when Muhammad arrived in Medina, he found people celebrating two specific days in which they entertained themselves with recreation. Muhammad then remarked that God had fixed two mandatory days of festivity: Eid al-Fitr and Eid al-Adha.

Eid al-Fitr begins at sunset on the night of the first sighting of the crescent moon. The night on which the moon is sighted is celebrated as Chand Raat in countries like Bangladesh. If the moon is not observed immediately after the 29th day of the previous lunar month (either because clouds block its view or because the western sky is still too bright when the moon sets), then the holiday is celebrated the following day. Eid al-Fitr is celebrated for one to three days, depending on the country. It is forbidden to fast on the Day of Eid, and a specific prayer is nominated for this day. As an obligatory act of charity, money is paid to the poor and the needy (zakat al-Fitr) before performing the 'Eid prayer.

The Eid prayer is performed by the congregation in an open area such as a field, community center, or mosque. No call to prayer is given for this Eid prayer, and it consists of only two rakaʿāt, with a variable amount of takbirs and other prayer elements depending on the branch of Islam observed. The Eid prayer is followed by the khutbah and then a dua asking for God's forgiveness, mercy, peace and blessings for all living beings across the world. The sermon also instructs Muslims as to the performance of rituals of Eid, such as the zakāt. The sermon of Eid takes place after the Eid prayer, unlike Friday prayer which comes first before prayer. Some imams believe that listening to the sermon at Eid is optional. After the prayers, Muslims visit their relatives, friends, and acquaintances or hold large communal celebrations in homes, community centers, or rented halls.

As ritual dictates, Sunnis praise God in a loud voice while going to the Eid prayer:

Allāhu Akbar, Allāhu Akbar, Allāhu Akbar. Lā ilāha illà l-Lāh. Allāhu Akbar, Allahu akbar, wa-li-l-Lāh al-ḥamd

Recitation ceases when they get to the place of Eid or once the Imam commences activities.