Short answer
The chest, back and shoulders are not part of a man's awrah, so going shirtless or wearing a tank top is not haram in itself. But it goes against modesty in public, so keep it for the pool, the beach, sport or home. In prayer, the Hanafi school dislikes leaving the shoulders bare when you have something to cover them, and the Hanbali school requires one shoulder covered in obligatory prayers.
A man's awrah is from the navel to below the knees, so exposing the upper body is not haram, though going about bare-chested in public is against good manners. Praying with the shoulders bare when one has a garment to cover them is makruh.
Other madhhabs
- Hanbali
- Covering at least one shoulder is a condition of obligatory prayers for a man who is able to.
Explanation
A man must cover from the navel to below the knees, and the Hanafi school counts the knees themselves as awrah; see the awrah guide. Anything above the navel is not awrah, so a man who takes off his shirt to swim, play sport or work in the heat has not sinned.
Modesty still matters. The Prophet ﷺ taught that modesty is a branch of faith. Walking around shirtless in streets, shops or mixed company is not the dress of dignified people, and it draws attention. Keep a shirt on in public and save going shirtless for the pool, the beach, sport or private settings. See haya in Islam.
Tank tops and short sleeves. T-shirts and short sleeves are fine. A sleeveless vest is allowed, but a tight, low-cut gym top worn to show off the body is better avoided, and very skimpy cuts start to copy women's fashion. Shorts must still cover the knees; see can men wear shorts.
In prayer. The Prophet said that none of you should pray in a single garment with nothing over his shoulders. The Hanafi texts dislike praying in only trousers or a waist wrap when you have a shirt, and the Hanbali school makes covering one shoulder a condition of obligatory prayers. Put a shirt on before you pray. See how to pray.
The evidence
Quran, Surah Al-A'raaf 7:26
يَٰبَنِىٓ ءَادَمَ قَدْ أَنزَلْنَا عَلَيْكُمْ لِبَاسًۭا يُوَٰرِى سَوْءَٰتِكُمْ وَرِيشًۭا ۖ وَلِبَاسُ ٱلتَّقْوَىٰ ذَٰلِكَ خَيْرٌۭ ۚ ذَٰلِكَ مِنْ ءَايَٰتِ ٱللَّهِ لَعَلَّهُمْ يَذَّكَّرُونَ ﴿٢٦﴾
O children of Adam, We have bestowed upon you clothing to conceal your private parts and as adornment. But the clothing of righteousness - that is best. That is from the signs of Allah that perhaps they will remember.
Dress serves modesty and taqwa, not only the minimum of covering.
Sahih al-Bukhari 359
Sahih... لا يصلي أحدكم في الثوب الواحد ليس على عاتقيه شيء ...
"None of you should pray in a single garment with nothing over his shoulders."
The shoulders should be covered in prayer when possible.
Sahih al-Bukhari 9
Sahih... والحياء شعبة من الإيمان ...
"And modesty is a branch of faith."
Modesty in dress goes beyond the minimum of the awrah.
Where the ruling is recorded
- al-Hidaya, Kitab al-Salah, chapter on the conditions of prayer. A man's awrah is from below the navel to the knee, with the knee included.
- al-Fatawa al-Hindiyya, Kitab al-Salah, chapter on what is disliked in prayer. Praying in only trousers or a waist wrap when other clothes are available is disliked.
- al-Mughni (Ibn Qudama), Kitab al-Salah, on covering the awrah. The Hanbali requirement to cover a shoulder in obligatory 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.