Here’s a simple, Jain-dharmic view of the three items you asked about and how they differ in the Śvetāmbara and Digambara traditions.

• Micchami Dukkadam

- What it is: A Prakrit phrase meaning “may all my bad deeds be fruitless” or “I seek forgiveness for any harm I may have caused.” It is spoken to ask forgiveness from others (and sometimes from all living beings) and to grant forgiveness in return. - When it’s used: On the last day of Paryushan for Śvetāmbara Jains (Samvatsari) and in related forgiveness moments during Pratikramana; in Digambara practice it is linked with Kshamavani as part of the Das Lakshana cycle. The core idea is universal forgiveness and self-purification. ( jainknowledge.com)

• Kshamavani (Forgiveness Day) in Digambara tradition

- What it is: The Forgiveness Day in the Digambara calendar, called Kshamavani Parva (Kṣamāvaṇī), marks forgiveness and repentance as the opening or central theme of their observance after the Paryushan-like period known as Das Lakshana Parva. - When it’s observed: It falls on the first day of Ashvin Krishna in the Digambara Jain calendar, and is the Digambara equivalent of the forgiveness focus that Śvetāmbara observe on Samvatsari, though the dates and naming differ. The practice includes saying Micchami Dukkadam and making heartfelt apologies and vows to improve. ( en.wikipedia.org) - Important note: While the wording and exact day differ, the spiritual aim is the same: cleanse karma through confession, forgiveness, and restraint. See cross‑sect explanations and the shared meaning of the day. ( jainknowledge.com)

• The 1st day of Digambar Paryushan (Das Lakshana Parva)

- What it is: In Digambara practice, Paryushan is called Das Lakshana Parva and lasts about 10 days, with each day focusing on one of ten virtues (dharma): Kshama (forgiveness), Mardava (humility), Arjava (straightforwardness), Shaucha (purity), Satya (truth), Sanyam (restraint), Tap (austerity), Tyag (renunciation), Akinchanya (non-attachment), Brahmacharya (chastity). - The 1st day’s focus: Kshama (forgiveness) is emphasized as the opening virtue; the community engages in reflection, confession, and vows to practice forgiveness more deeply during these days. So, the 1st day anchors the entire Das Lakshana practice around forgiveness, before moving through the other virtues. ( jainknowledge.com)

How they relate to each other (in short)

• Both traditions aim for forgiveness, introspection, and purification during Paryushan/Das Lakshana.
• Micchami Dukkadam is the common refrain used to seek forgiveness and to grant forgiveness, but the formal day names shift:

- Śvetāmbara: Samvatsari (last day of eight‑day Paryushan) is the forgiveness day. Micchami Dukkadam is exchanged then. ( jainknowledge.com) - Digambara: Kshamavani Parva (first day of Ashvin Krishna) is the forgiveness day. Micchami Dukkadam is still the phrase used, but the day differs. ( en.wikipedia.org)

If you’d like, I can provide the exact wording for Micchami Dukkadam as used in Śvetāmbara and Digambara practice, along with the original mantras and a simple pronunciation guide.