In Jainism there isn’t a single universal “certificate” or outside authority that formally appoints someone as a Jain. Being Jain is about following the Dharma and being recognized by one’s own conduct and by the Jain community.

Key points:

• Core identity: A Jain is someone who embraces the Jain worldview—belief in the 24 Tirthankaras, and follows the three aims (artha, rta, satya) through the Jain path of ahimsa (non-violence), satya (truth), asteya (non-stealing), brahmacharya (celibacy or fidelity, for laypeople), and aparigraha (non-attachment).
• Lay (upāsak/upāsika) practice: A Jain layperson commits to the five main vows (ahimsa, satya, asteya, brahmacharya in conduct, and aparigraha) and regularly engages in Jain practices such as samayik (meditative time for reflection), pratikraman (confession and repentance), fasting, and temple/community involvement.
• Monastic initiation: A formal Diksha (monastic order initiation) occurs when a person becomes a monk or nun. This is a formal, recognized transition within the Jain Sangh (community) and involves taking explicit vows and following a stricter code of conduct.
• No universal clergy endorsement: Outside of Diksha, there is no single global council that “approves” or “recognizes” every individual as Jain. While temples, communities, and lineages may have local acknowledgments or traditions, the essential recognition comes from living the Jain path and being accepted by one’s Jain community.
• Digambar vs. Shwetambar: Both traditions consider someone a Jain who follows the Jain path and the vows appropriate to their stage of life. There are tradition-specific practices and interpretations, but the basic criterion—adhesion to Jain dharma and recognition by the Jain community—remains the same.

In short, you are Jain by embracing and living the Jain path with sincerity, and by being accepted as part of a Jain community. If you’re exploring, you can look into how the five vows and practices like samayik and pratikraman are observed in daily life, and what Diksha involves for those drawn to monastic life.