Are tattoos allowed in Islam?
No they are not. Let us look at what Prophet Muhammad peace be upon commanded:
Narrated 'Abdullah bin Yazid Al-Ansari: "The Prophet forbade robbery (taking away what belongs to others without their permission), and also forbade mutilation (or maiming) of bodies. (Translation of Sahih Bukhari, Oppressions, Volume 3, Book 43, Number 654)"
The following several narrations of Prophet Muhammad peace be upon him were sent to me by Omar; may Allah Almighty always be pleased with him:
Narrated Abu Huraira: "Allah's Apostle said, 'The evil eye is a fact,' and he forbade tattooing. (Translation of Sahih Bukhari, Dress, Volume 7, Book 72, Number 827)"
Narrated 'Aun bin Abu Juhaifa: "My father bought a slave who practiced the profession of cupping. (My father broke the slave's instruments of cupping). I asked my father why he had done so. He replied, 'The Prophet forbade the acceptance of the price of a dog or blood, and also forbade the profession of tattooing, getting tattooed and receiving or giving Riba, (usury), and cursed the picture-makers.' (Translation of Sahih Bukhari, Sales and Trade, Volume 3, Book 34, Number 299)"
Narrated 'Abdullah: "Allah has cursed those women who practise tattooing and those who get themselves tattooed, and those who remove their face hairs, and those who create a space between their teeth artificially to look beautiful, and such women as change the features created by Allah. Why then should I not curse those whom the Prophet has cursed? And that is in Allah's Book. i.e. His Saying: 'And what the Apostle gives you take it and what he forbids you abstain (from it).' (59.7) (Translation of Sahih Bukhari, Dress, Volume 7, Book 72, Number 815)"
As you can see, any type of body mutilation or maiming even if it were a small tattoo is clearly prohibited in Islam.
In Islam, we follow the laws of the Noble Quran, and the Sayings of Prophet Muhammad peace be upon him.
If a situation or case is not addressed in neither the Noble Quran, or the Sayings of our beloved Prophet, then we follow the local verdicts of our Religious Authorities, where they would decide based upon the cultural and social situation and causes.
It is a must for us to follow the commands of our beloved Prophet peace be upon him, thus in this case, mutilation or maiming of any type to the human body and tattooing are prohibited.
Hope this answered ur question :)