In general, Iran issues 13 types of visa for applicants :
The Islamic Republic of Iran issued an airport visa permit for some nationals from different countries. According to this, all visa and passports offices of the Ministry of Foreign Affairs based at Imam Khomeini, Mehrabad, Mashhad, Shiraz and Tabriz airports can issue visa on arrival to tourists . it should be noted that this type of visa is issued solely for the purpose of tourism.
Given the international agreements of Iran with some countries, it is possible to enter to Iran for the citizens of some countries without a visa.