How do I know if my ancestor died on Ashtami Tithi?

If you have the English calendar date of your ancestor’s death, you can convert it to the Hindu Panchang tithi using any Hindu calendar converter (drikpanchang.com is reliable). Enter the death date and it will show the corresponding tithi. If you don’t have the death date at all, use Sarva Pitru Amavasya (October 10, 2026) as your primary Shradh day, which covers all tithis.