In Jainism, “Jain” is not a caste – it is a religion (Dharma).

• Jain means a follower of Jain Dharma, not a member of any fixed caste.
• Jains can come from many social communities (Oswal, Porwal, Agarwal, Khandelwal, etc.). These are community/jāti names, not one single “Jain caste” for everyone. ( jainknowledge.com)
• Spiritually, Jain scriptures teach that all souls are equal and progress depends on karma and effort, not on birth or caste.

So, to your question “Jain comes under which caste category?”:

• Religiously: Jain = a separate religion, not a caste.
• Socially (in India): Jains may belong to different trading or regional communities, but these are social labels, not part of Jain spiritual doctrine.

You can read a simple explanation here