People planning to visit Thailand for a short period of within 30 days can apply for a Tourist visa which permits an applicant to stay for a maximum of 60 days. The cost of a Tourist visa is 1,000 Baht per entry. The documents required for the visa are

• Passport or travel document with validity not less than 6 months. 
• Visa application form completely filled out.
• Recent (4 x 6 cm.) photograph of the applicant. 
• Evidence of travel from Thailand (air ticket paid in full). 
• Evidence of adequate finance (10,000 Baht per person and 20,000 Baht per family). 
• A conference invitation letter from the conference organizer.

For more information on visa application, please visit the below mentioned link.

http://www.thaiembassy.sg/tourist-visa