According to Jainism, its history is beginningless (anādi), so in the real Jain view you cannot put an age on it.

Jain Dharm teaches:

1. Jainism is eternal

- The universe and the laws of karma and dharma have always existed. - In every time‑cycle there are 24 Tirthankars who rediscover and teach this eternal path.

1. In the present time‑cycle (avasarpiṇī)

- The 1st Tirthankar is Bhagwan Ṛṣabhdev (Ādināth) – said to have lived in very ancient times, far beyond normal historical dating. - The 24th Tirthankar, Bhagwan Mahavir, lived about 2600 years ago (6th century BCE). - So from a modern “history book” view, people usually say Jainism is at least 2500–3000 years old, but - From the Jain spiritual view, Jainism is much, much older and actually timeless.

So, in simple words:

• Historian’s answer: at least ~3000 years old.
• Jain Dharm’s own answer: Jainism has no beginning; it is eternal and has been taught by countless Tirthankars over unimaginable time.

You can read a short explanation in simple language here: “When did Jainism start?”