Nepali Visa

Visa Requirements : http://www.nepalimmigration.gov.np/page/tourist-visa  

All foreigners require a visa for entry into Nepal.  You can get from a Nepalese embassy overseas or on arrival in Nepal. Most people will obtain their visa on arrival to Kathmandu airport.  For obtaining the visa your passport should have atleast 6 months validity on the day of departure, one passport size photograph and the visa fee on US $ cash.

15 days USD$ 30 or equivalent convertible currency

30 days USD$  50 or equivalent convertible currency

90 days USD$125 or equivalent convertible currency

Also you can now a days apply the visa online prior to your arrival in Kathmandu. Online Services (immigration.gov.np)