In Jain Dharma, many religious observances are based on tithis in the lunar calendar. Common important tithi-based days include:

• Ashtami – often observed for fasting, worship, and spiritual discipline.
• Chaturdashi – especially important for Pancham, Ashtahnika, and monthly vrat observances in some traditions.
• Purnima – full moon day; considered auspicious for worship and religious activities.
• Amavasya – new moon day; also important for fasting and devotion.
• Ekadashi – observed by many for vows and spiritual practice.
• Trayodashi / Chaturdashi – in some traditions, special for observances and vrata.
• Panchami – important in some Jain observances.
• Saptami / Ashtami / Chaturdashi – often used for regular religious vows and austerities.

Some especially important Jain tithi-based observances are:

• Paryushan / Das Lakshan period
• Samvatsari or Kshamavani day
• Mahavir Janma Kalyanak
• Nirvan Kalyanak days of Tirthankars
• Akshaya Tritiya for special remembrance of Lord Rishabhdev’s ahar-daan
• Kartik Purnima, Maagh Purnima, and other monthly sacred days in different traditions

Different Jain traditions may follow slightly different tithi practices, especially Digambar and Shwetambar traditions.

If you want, I can also give you a month-wise list of major Jain tithi days in simple format.