There is no age limit for NATA exam. You just need to complete your 10+2 standard exam from any recognized board with subjects including physics, chemistry and mathematics. 

ABOUT NATA

NATA, National aptitude test for architecture, is an entrance exam which is conducted by National Institute of advanced studies in architecture (NIASA) the body of council of Architecture in India. This entrance exam is a national level examination. Students who are willing to study Bachelor of architecture or some other relevant architecture courses at all recognized institutions across India, can give NATA after their 12th examination.
NATA measures drawing and observation skills, sense of proportion, aesthetic sensitivity and critical thinking ability.

NATA is 3 hour test within which candidates have to answer 125 questions. There will be 1 mark, 2 marks and 3 marks questions. Candidates will have to answer 75 one mark questions, 25 two marks questions and 25 three marks questions. Total 200 questions and 200 marks examination. Duration of exam is for 3 hours. The entire question paper will be in English and  there is no negative marking. 

If a candidate willing to crack NATA, he/she have to know well about NATA entrance’s eligibility criteria very well. It will help them to prepare for the examination. 

ELIGIBILITY CRITERIA FOR NATA

NATA Eligibility Criteria is divided into 4 sections such as age, qualification, subject, minimum marks. The candidates must be eligible for all the 4 sections in order to qualify NATA. 

• Age- Fortunately, there is no age limit now to qualify NATA. 
• Qualification- Qualifying 10+2 examination in with the subjects Physics Chemistry maths from any recognized board is must for the candidates. Or candidates who have qualified 10+3 with mathematics from any recognized board can also eligible for NATA. 
• Subject- The candidates must have Physics, chemistry and mathematics as a mandatory subjects to be eligible for NATA. candidates from arts stream can be eligible too only if they are qualified the physics, chemistry and mathematics exams conducted by CBSC
• Marks- The candidates must score minimum of 50% marks in their qualifying examination and 50% marks in Physics, chemistry and maths. 5% relaxation has been given to SC, ST, OBC-NCL category or PwD candidates.

Hope this helps! 
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See the application fees structure for NATA, 

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