Short answer
Only in salah, and only in the Hanafi school. Laughing out loud during a prayer with ruku and sajdah breaks both the prayer and wudu. Laughing outside prayer never breaks wudu. The other three schools say laughter breaks the prayer but not wudu.
Loud laughter (qahqahah) that people next to you can hear, by an adult who is awake, in a prayer with ruku and sajdah, breaks both the prayer and wudu. Laughter only you can hear breaks the prayer but not wudu. A smile breaks neither.
Other madhhabs
- Shafi'i
- Laughter breaks the prayer if it produces letters or is loud, but it never breaks wudu.
- Maliki
- Laughter breaks the prayer but not wudu.
- Hanbali
- Laughter breaks the prayer but not wudu.
Explanation
This is one of the rulings special to the Hanafi school. It rests on reports that some people laughed out loud behind the Prophet ﷺ in prayer when a man with poor sight fell into a pit, and that they were told to repeat both wudu and prayer. These reports reach us mostly as mursal narrations (passed on by a Successor who does not name the Companion), collected by al-Daraqutni and others. The Hanafi school accepts a strong mursal report and holds that a Companion would not make up a ruling like this, which goes against analogy. The other schools judge the reports too weak to change wudu.
The Hanafi levels:
- Smiling (tabassum): no sound. Breaks nothing.
- Laughing (dahik): you hear it but the person next to you does not. Breaks the prayer, not wudu.
- Loud laughter (qahqahah): those near you hear it. Breaks the prayer and wudu.
The wudu ruling applies only in a prayer with ruku and sajdah. Loud laughter in the funeral prayer or in a sajdah of recitation breaks that prayer or sajdah but not wudu. It does not apply to a child or to someone who laughs in their sleep during prayer.
Outside salah, laughing, joking or giggling does not break wudu in any school.
The evidence
Quran, Surah Al-Baqara 2:238
حَٰفِظُوا۟ عَلَى ٱلصَّلَوَٰتِ وَٱلصَّلَوٰةِ ٱلْوُسْطَىٰ وَقُومُوا۟ لِلَّهِ قَٰنِتِينَ ﴿٢٣٨﴾
Maintain with care the [obligatory] prayers and [in particular] the middle prayer and stand before Allah, devoutly obedient.
Prayer is a state of humble standing before Allah, which loud laughter breaks.
Quran, Surah Al-Muminoon 23:2
ٱلَّذِينَ هُمْ فِى صَلَاتِهِمْ خَٰشِعُونَ ﴿٢﴾
They who are during their prayer humbly submissive
Describes the humility that belongs in salah.
Where the ruling is recorded
- al-Hidaya, Kitab al-Taharat, chapter on what breaks wudu. Loud laughter in a prayer with ruku and sajdah breaks wudu.
- Radd al-Muhtar (Ibn Abidin), Kitab al-Taharah, nawaqid al-wudu. The levels of laughter and the conditions for the ruling.
- al-Mughni (Ibn Qudama), Kitab al-Taharah, chapter on what breaks wudu. The view of the other schools that laughter does not break wudu.
This answer is pending review by the scholars on our team. Quran translation by Sahih International. Hadith Arabic from the standard editions of the six books and the Muwatta, with gradings as recorded there; the English is our own rendering. Spotted a mistake? Tell us.