Answer

On Janm Kalyanak, the most common and most auspicious jaap is Navkar Mantra.

Explanation

Devotees also chant:

• Namo Arihantanam
• Navkar Mantra
• Jai Jinendra
• Stavan / Bhakti geet for the Tirthankar

If you are observing Janm Kalyanak of a Tirthankar, then Navkar Mantra jaap is the safest and most universally accepted choice in Jain Dharma.

Spiritual Understanding

Janm Kalyanak is a day of deep reverence and celebration of a Tirthankar’s sacred birth. Jaap on this day is done to:

• remember the virtues of the Tirthankar
• purify the mind
• increase devotion
• invite inner peace and spiritual upliftment

Takeaway

If you want one simple answer: do Navkar Mantra jaap on Janm Kalyanak.