Wudu is washing the face and the arms to the elbows, wiping the head and washing the feet to the ankles, as the Quran commands for the one who stands to pray (5:6). It is a condition for the prayer to be valid: the Prophet ﷺ said that no prayer is accepted without purification.
1The obligatory parts
Washing the whole face, from the hairline to the chin and from ear to ear.
Washing both arms, including the elbows.
Wiping the head.
Washing both feet, including the ankles.
These four are named in the verse. Most scholars add the intention, doing the parts in order and without a long gap. See the differences below.
2The sunnah acts, as in the wudu of the Prophet ﷺ
Saying Bismillah at the start, and using the siwak.
Washing the hands three times first.
Rinsing the mouth and nose, sniffing water in and blowing it out.
Washing each part three times (once is enough, twice is also reported).
Wiping the whole head from the front to the back and back again, and wiping the ears.
Starting with the right side, and saying the shahada when finished.
3What breaks wudu (agreed)
Anything that comes out of the front or back passage: urine, stool, wind, madhy and wady.
Losing awareness: deep sleep, fainting, madness or intoxication.
Where the schools differ
The four Sunni schools agree on the main ruling above and differ in these points. No school is preferred here.
Touching the private part. it breaks wudu in the Shafi'i and Hanbali schools, and in the Maliki school if done with desire. In the Hanafi school it does not.
Eating camel meat. it breaks wudu in the Hanbali school. The other schools say it does not.
Flowing blood or vomiting. it breaks wudu in the Hanafi school, and in the Hanbali school if it is a lot. In the Maliki and Shafi'i schools it does not.
Touching a woman. it breaks wudu in the Shafi'i school, in the Maliki and Hanbali schools only if with desire, and in the Hanafi school it does not.
The intention (niyyah) is a condition of wudu in the Maliki, Shafi'i and Hanbali schools. The Hanafi school holds that it is recommended for wudu with water.
Note
If you were sure you had wudu and only doubt whether it was broken, you stay in wudu. Doubt does not remove certainty.
O you who have believed, when you rise to [perform] prayer, wash your faces and your forearms to the elbows and wipe over your heads and wash your feet to the ankles. And if you are in a state of janabah, then purify yourselves. But if you are ill or on a journey or one of you comes from the place of relieving himself or you have contacted women and do not find water, then seek clean earth and wipe over your faces and hands with it. Allah does not intend to make difficulty for you, but He intends to purify you and complete His favor upon you that you may be grateful.
And they ask you about menstruation. Say, "It is harm, so keep away from wives during menstruation. And do not approach them until they are pure. And when they have purified themselves, then come to them from where Allah has ordained for you. Indeed, Allah loves those who are constantly repentant and loves those who purify themselves."
From the Sunnah
Sahih Muslim 224aAuthentic collection
The point of the hadith: No prayer is accepted without purification.
The point of the hadith: Uthman showed how the Prophet ﷺ made wudu, and the Prophet ﷺ said that whoever makes wudu like this and prays two rak'ahs with full attention will have his past sins forgiven.
This is general information, not a fatwa. For your own situation, ask a qualified scholar.
Fiqh questions
Wudu (ablution): how to perform it and what breaks it
Wudu is washing the face and the arms to the elbows, wiping the head and washing the feet to the ankles, as the Quran commands for the one who stands to pray (5:6). It is a condition for the prayer to be valid: the Prophet ﷺ said that no prayer is accepted without purification.
Is this a fatwa?
No. It is a summary of well-known rulings with their evidence. For your own case, ask a qualified scholar.
What if my school differs from this answer?
Follow the view of the school you follow and the scholar who teaches you. The page lists the differences of the four schools.