Short answer
Rolling up your sleeves for prayer, or praying with them still rolled up after wudu, is makruh in the Hanafi school, so roll them down first. A shirt that simply has short sleeves is valid, and many muftis consider it only mildly disliked if you have fuller clothes. A sleeveless vest that leaves the shoulders bare is more clearly disliked.
Folding back or gathering up the clothes (kaff al-thawb), such as rolled-up sleeves, is makruh, and many Hanafi muftis class it as makruh tahrimi, advising that the prayer be repeated within its time. Praying in clothes you would not wear before respected people, such as a vest or work clothes, is makruh tanzihi when better clothes are available.
Other madhhabs
- Hanbali
- A man must cover at least one shoulder in a fard prayer if he is able; praying with both shoulders bare is not valid.
- Shafi'i
- Rolling up the sleeves or tucking up the clothes is mildly disliked.
Explanation
For men, the awrah (what must be covered) is from the navel to below the knee, so bare arms or shoulders do not make the prayer invalid in the Hanafi school. The question is whether it is disliked, and that depends on how the arms came to be bare.
Rolled-up sleeves. The Prophet ﷺ said he was commanded to prostrate on seven bones and not to fold back his hair or clothes. Hanafi scholars include rolling up the sleeves in this. Many people make wudu and walk straight into prayer with their sleeves pushed up; roll them down before the opening takbir.
- Short-sleeved shirt: valid. It is better to pray in fuller clothes, and many muftis call a short-sleeved shirt mildly disliked when you have something better.
- Vest or tank top: disliked, since bare shoulders are not how you would dress to meet someone you respect. Allah says to take your adornment at every masjid.
- Shorts: a different issue, since the knees are awrah; see can you pray in shorts.
For women's sleeves and arms, see can a woman pray with her feet or hands uncovered. The awrah in full is on awrah for men and women.
The evidence
Quran, Surah Al-A'raaf 7:31
۞ يَٰبَنِىٓ ءَادَمَ خُذُوا۟ زِينَتَكُمْ عِندَ كُلِّ مَسْجِدٍۢ وَكُلُوا۟ وَٱشْرَبُوا۟ وَلَا تُسْرِفُوٓا۟ ۚ إِنَّهُۥ لَا يُحِبُّ ٱلْمُسْرِفِينَ ﴿٣١﴾
O children of Adam, take your adornment at every masjid, and eat and drink, but be not excessive. Indeed, He likes not those who commit excess.
Dress well and modestly for prayer.
Sahih al-Bukhari 816
Sahih... أمرت أن أسجد على سبعة لا أكف شعرا ولا ثوبا ...
"I was commanded to prostrate on seven bones and not to fold back hair or clothes."
Folding back the clothes, such as rolling up sleeves, is disliked in prayer.
Where the ruling is recorded
- Nur al-Idah with Maraqi al-Falah, Chapter on what is disliked in prayer. Folding back the clothes and praying in work clothes are among the disliked acts.
- Radd al-Muhtar (Ibn Abidin), Kitab al-Salah, chapter on what is disliked in prayer. Discusses rolling up the sleeves before or during prayer.
- al-Mughni (Ibn Qudama), Chapter on covering the awrah. The Hanbali requirement to cover a shoulder in fard prayer.
Checked by our team. For a more accurate answer to your own situation, consult a scholar. 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.